Re: Asynchronous Append on postgres_fdw nodes.
| От | Kyotaro Horiguchi |
|---|---|
| Тема | Re: Asynchronous Append on postgres_fdw nodes. |
| Дата | |
| Msg-id | 20200610.120510.2075667454883130505.horikyota.ntt@gmail.com обсуждение исходный текст |
| Ответ на | Re: Asynchronous Append on postgres_fdw nodes. (Andrey Lepikhov <a.lepikhov@postgrespro.ru>) |
| Ответы |
Re: Asynchronous Append on postgres_fdw nodes.
("Andrey V. Lepikhov" <a.lepikhov@postgrespro.ru>)
Re: Asynchronous Append on postgres_fdw nodes. ("Andrey V. Lepikhov" <a.lepikhov@postgrespro.ru>) Re: Asynchronous Append on postgres_fdw nodes. (Kyotaro Horiguchi <horikyota.ntt@gmail.com>) |
| Список | pgsql-hackers |
Hello, Andrey.
At Tue, 9 Jun 2020 14:20:42 +0500, Andrey Lepikhov <a.lepikhov@postgrespro.ru> wrote in
> On 6/4/20 11:00 AM, Kyotaro Horiguchi wrote:
> > Removed a useless variable PgFdwScanState.result_ready.
> > Removed duplicate code from remove_async_node() by using
> > move_to_next_waiter().
> > Done some minor cleanups.
> >
> I am reviewing your code.
> A couple of variables are no longer needed (see changes.patch in
> attachment.
Thanks! The recent changes made them useless. Fixed.
> Something about the cost of an asynchronous plan:
>
> At the simple query plan (see below) I see:
> 1. Startup cost of local SeqScan is equal 0, ForeignScan - 100. But
> startup cost of Append is 0.
The result itself is right that the append doesn't wait for foreign
scans for the first iteration then fetches a tuple from the local
table. But the estimation is made just by an accident. If you
defined a foreign table as the first partition, the cost of Append
would be 100, which is rather wrong.
> 2. Total cost of an Append node is a sum of the subplans. Maybe in the
> case of asynchronous append we need to use some reduce factor?
Yes. For the reason mentioned above, foreign subpaths don't affect
the startup cost of Append as far as any sync subpaths exist. If no
sync subpaths exist, the Append's startup cost is the minimum startup
cost among the async subpaths.
I fixed cost_append so that it calculates the correct startup
cost. Now the function estimates as follows.
Append (Foreign(100), Foreign(100), Local(0)) => 0;
Append (Local(0), Foreign(100), Foreign(100)) => 0;
Append (Foreign(100), Foreign(100)) => 100;
> explain select * from parts;
>
> With Async Append:
> =====================
>
> Append (cost=0.00..2510.30 rows=106780 width=8)
> Async subplans: 3
> -> Async Foreign Scan on part_1 parts_2 (cost=100.00..177.80 rows=2260
> -> width=8)
> -> Async Foreign Scan on part_2 parts_3 (cost=100.00..177.80 rows=2260
> -> width=8)
> -> Async Foreign Scan on part_3 parts_4 (cost=100.00..177.80 rows=2260
> -> width=8)
> -> Seq Scan on part_0 parts_1 (cost=0.00..1443.00 rows=100000 width=8)
The SeqScan seems to be the first partition for the parent. It is the
first subnode at cost estimation. The result is right but it comes
from a wrong logic.
> Without Async Append:
> =====================
>
> Append (cost=0.00..2510.30 rows=106780 width=8)
> -> Seq Scan on part_0 parts_1 (cost=0.00..1443.00 rows=100000 width=8)
> -> Foreign Scan on part_1 parts_2 (cost=100.00..177.80 rows=2260 width=8)
> -> Foreign Scan on part_2 parts_3 (cost=100.00..177.80 rows=2260 width=8)
> -> Foreign Scan on part_3 parts_4 (cost=100.00..177.80 rows=2260 width=8)
The starup cost of the Append is the cost of the first subnode, that is, 0.
regards.
--
Kyotaro Horiguchi
NTT Open Source Software Center
From 281ed344f13352dd00bd08926fd8dd12ae182d01 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Mon, 22 May 2017 12:42:58 +0900
Subject: [PATCH v4 1/3] Allow wait event set to be registered to resource
owner
WaitEventSet needs to be released using resource owner for a certain
case. This change adds WaitEventSet reowner and allow the creator of a
WaitEventSet to specify a resource owner.
---
src/backend/libpq/pqcomm.c | 2 +-
src/backend/storage/ipc/latch.c | 18 ++++-
src/backend/storage/lmgr/condition_variable.c | 2 +-
src/backend/utils/resowner/resowner.c | 67 +++++++++++++++++++
src/include/storage/latch.h | 4 +-
src/include/utils/resowner_private.h | 8 +++
6 files changed, 96 insertions(+), 5 deletions(-)
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 7717bb2719..16aefb03ee 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -218,7 +218,7 @@ pq_init(void)
(errmsg("could not set socket to nonblocking mode: %m")));
#endif
- FeBeWaitSet = CreateWaitEventSet(TopMemoryContext, 3);
+ FeBeWaitSet = CreateWaitEventSet(TopMemoryContext, NULL, 3);
AddWaitEventToSet(FeBeWaitSet, WL_SOCKET_WRITEABLE, MyProcPort->sock,
NULL, NULL);
AddWaitEventToSet(FeBeWaitSet, WL_LATCH_SET, -1, MyLatch, NULL);
diff --git a/src/backend/storage/ipc/latch.c b/src/backend/storage/ipc/latch.c
index 91fa4b619b..10d71b46cb 100644
--- a/src/backend/storage/ipc/latch.c
+++ b/src/backend/storage/ipc/latch.c
@@ -56,6 +56,7 @@
#include "storage/latch.h"
#include "storage/pmsignal.h"
#include "storage/shmem.h"
+#include "utils/resowner_private.h"
/*
* Select the fd readiness primitive to use. Normally the "most modern"
@@ -84,6 +85,8 @@ struct WaitEventSet
int nevents; /* number of registered events */
int nevents_space; /* maximum number of events in this set */
+ ResourceOwner resowner; /* Resource owner */
+
/*
* Array, of nevents_space length, storing the definition of events this
* set is waiting for.
@@ -393,7 +396,7 @@ WaitLatchOrSocket(Latch *latch, int wakeEvents, pgsocket sock,
int ret = 0;
int rc;
WaitEvent event;
- WaitEventSet *set = CreateWaitEventSet(CurrentMemoryContext, 3);
+ WaitEventSet *set = CreateWaitEventSet(CurrentMemoryContext, NULL, 3);
if (wakeEvents & WL_TIMEOUT)
Assert(timeout >= 0);
@@ -560,12 +563,15 @@ ResetLatch(Latch *latch)
* WaitEventSetWait().
*/
WaitEventSet *
-CreateWaitEventSet(MemoryContext context, int nevents)
+CreateWaitEventSet(MemoryContext context, ResourceOwner res, int nevents)
{
WaitEventSet *set;
char *data;
Size sz = 0;
+ if (res)
+ ResourceOwnerEnlargeWESs(res);
+
/*
* Use MAXALIGN size/alignment to guarantee that later uses of memory are
* aligned correctly. E.g. epoll_event might need 8 byte alignment on some
@@ -680,6 +686,11 @@ CreateWaitEventSet(MemoryContext context, int nevents)
StaticAssertStmt(WSA_INVALID_EVENT == NULL, "");
#endif
+ /* Register this wait event set if requested */
+ set->resowner = res;
+ if (res)
+ ResourceOwnerRememberWES(set->resowner, set);
+
return set;
}
@@ -725,6 +736,9 @@ FreeWaitEventSet(WaitEventSet *set)
}
#endif
+ if (set->resowner != NULL)
+ ResourceOwnerForgetWES(set->resowner, set);
+
pfree(set);
}
diff --git a/src/backend/storage/lmgr/condition_variable.c b/src/backend/storage/lmgr/condition_variable.c
index 37b6a4eecd..fcc92138fe 100644
--- a/src/backend/storage/lmgr/condition_variable.c
+++ b/src/backend/storage/lmgr/condition_variable.c
@@ -70,7 +70,7 @@ ConditionVariablePrepareToSleep(ConditionVariable *cv)
{
WaitEventSet *new_event_set;
- new_event_set = CreateWaitEventSet(TopMemoryContext, 2);
+ new_event_set = CreateWaitEventSet(TopMemoryContext, NULL, 2);
AddWaitEventToSet(new_event_set, WL_LATCH_SET, PGINVALID_SOCKET,
MyLatch, NULL);
AddWaitEventToSet(new_event_set, WL_EXIT_ON_PM_DEATH, PGINVALID_SOCKET,
diff --git a/src/backend/utils/resowner/resowner.c b/src/backend/utils/resowner/resowner.c
index 8bc2c4e9ea..237ca9fa30 100644
--- a/src/backend/utils/resowner/resowner.c
+++ b/src/backend/utils/resowner/resowner.c
@@ -128,6 +128,7 @@ typedef struct ResourceOwnerData
ResourceArray filearr; /* open temporary files */
ResourceArray dsmarr; /* dynamic shmem segments */
ResourceArray jitarr; /* JIT contexts */
+ ResourceArray wesarr; /* wait event sets */
/* We can remember up to MAX_RESOWNER_LOCKS references to local locks. */
int nlocks; /* number of owned locks */
@@ -175,6 +176,7 @@ static void PrintTupleDescLeakWarning(TupleDesc tupdesc);
static void PrintSnapshotLeakWarning(Snapshot snapshot);
static void PrintFileLeakWarning(File file);
static void PrintDSMLeakWarning(dsm_segment *seg);
+static void PrintWESLeakWarning(WaitEventSet *events);
/*****************************************************************************
@@ -444,6 +446,7 @@ ResourceOwnerCreate(ResourceOwner parent, const char *name)
ResourceArrayInit(&(owner->filearr), FileGetDatum(-1));
ResourceArrayInit(&(owner->dsmarr), PointerGetDatum(NULL));
ResourceArrayInit(&(owner->jitarr), PointerGetDatum(NULL));
+ ResourceArrayInit(&(owner->wesarr), PointerGetDatum(NULL));
return owner;
}
@@ -553,6 +556,16 @@ ResourceOwnerReleaseInternal(ResourceOwner owner,
jit_release_context(context);
}
+
+ /* Ditto for wait event sets */
+ while (ResourceArrayGetAny(&(owner->wesarr), &foundres))
+ {
+ WaitEventSet *event = (WaitEventSet *) DatumGetPointer(foundres);
+
+ if (isCommit)
+ PrintWESLeakWarning(event);
+ FreeWaitEventSet(event);
+ }
}
else if (phase == RESOURCE_RELEASE_LOCKS)
{
@@ -725,6 +738,7 @@ ResourceOwnerDelete(ResourceOwner owner)
Assert(owner->filearr.nitems == 0);
Assert(owner->dsmarr.nitems == 0);
Assert(owner->jitarr.nitems == 0);
+ Assert(owner->wesarr.nitems == 0);
Assert(owner->nlocks == 0 || owner->nlocks == MAX_RESOWNER_LOCKS + 1);
/*
@@ -752,6 +766,7 @@ ResourceOwnerDelete(ResourceOwner owner)
ResourceArrayFree(&(owner->filearr));
ResourceArrayFree(&(owner->dsmarr));
ResourceArrayFree(&(owner->jitarr));
+ ResourceArrayFree(&(owner->wesarr));
pfree(owner);
}
@@ -1370,3 +1385,55 @@ ResourceOwnerForgetJIT(ResourceOwner owner, Datum handle)
elog(ERROR, "JIT context %p is not owned by resource owner %s",
DatumGetPointer(handle), owner->name);
}
+
+/*
+ * wait event set reference array.
+ *
+ * This is separate from actually inserting an entry because if we run out
+ * of memory, it's critical to do so *before* acquiring the resource.
+ */
+void
+ResourceOwnerEnlargeWESs(ResourceOwner owner)
+{
+ ResourceArrayEnlarge(&(owner->wesarr));
+}
+
+/*
+ * Remember that a wait event set is owned by a ResourceOwner
+ *
+ * Caller must have previously done ResourceOwnerEnlargeWESs()
+ */
+void
+ResourceOwnerRememberWES(ResourceOwner owner, WaitEventSet *events)
+{
+ ResourceArrayAdd(&(owner->wesarr), PointerGetDatum(events));
+}
+
+/*
+ * Forget that a wait event set is owned by a ResourceOwner
+ */
+void
+ResourceOwnerForgetWES(ResourceOwner owner, WaitEventSet *events)
+{
+ /*
+ * XXXX: There's no property to show as an identier of a wait event set,
+ * use its pointer instead.
+ */
+ if (!ResourceArrayRemove(&(owner->wesarr), PointerGetDatum(events)))
+ elog(ERROR, "wait event set %p is not owned by resource owner %s",
+ events, owner->name);
+}
+
+/*
+ * Debugging subroutine
+ */
+static void
+PrintWESLeakWarning(WaitEventSet *events)
+{
+ /*
+ * XXXX: There's no property to show as an identier of a wait event set,
+ * use its pointer instead.
+ */
+ elog(WARNING, "wait event set leak: %p still referenced",
+ events);
+}
diff --git a/src/include/storage/latch.h b/src/include/storage/latch.h
index 46ae56cae3..b1b8375768 100644
--- a/src/include/storage/latch.h
+++ b/src/include/storage/latch.h
@@ -101,6 +101,7 @@
#define LATCH_H
#include <signal.h>
+#include "utils/resowner.h"
/*
* Latch structure should be treated as opaque and only accessed through
@@ -163,7 +164,8 @@ extern void DisownLatch(Latch *latch);
extern void SetLatch(Latch *latch);
extern void ResetLatch(Latch *latch);
-extern WaitEventSet *CreateWaitEventSet(MemoryContext context, int nevents);
+extern WaitEventSet *CreateWaitEventSet(MemoryContext context,
+ ResourceOwner res, int nevents);
extern void FreeWaitEventSet(WaitEventSet *set);
extern int AddWaitEventToSet(WaitEventSet *set, uint32 events, pgsocket fd,
Latch *latch, void *user_data);
diff --git a/src/include/utils/resowner_private.h b/src/include/utils/resowner_private.h
index a781a7a2aa..7d19dadd57 100644
--- a/src/include/utils/resowner_private.h
+++ b/src/include/utils/resowner_private.h
@@ -18,6 +18,7 @@
#include "storage/dsm.h"
#include "storage/fd.h"
+#include "storage/latch.h"
#include "storage/lock.h"
#include "utils/catcache.h"
#include "utils/plancache.h"
@@ -95,4 +96,11 @@ extern void ResourceOwnerRememberJIT(ResourceOwner owner,
extern void ResourceOwnerForgetJIT(ResourceOwner owner,
Datum handle);
+/* support for wait event set management */
+extern void ResourceOwnerEnlargeWESs(ResourceOwner owner);
+extern void ResourceOwnerRememberWES(ResourceOwner owner,
+ WaitEventSet *);
+extern void ResourceOwnerForgetWES(ResourceOwner owner,
+ WaitEventSet *);
+
#endif /* RESOWNER_PRIVATE_H */
--
2.18.2
From 4a172f8009b881ac17ebabcf5f12b0fccca004ba Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Tue, 15 May 2018 20:21:32 +0900
Subject: [PATCH v4 2/3] infrastructure for asynchronous execution
This patch add an infrastructure for asynchronous execution. As a PoC
this makes only Append capable to handle asynchronously executable
subnodes.
---
src/backend/commands/explain.c | 17 ++
src/backend/executor/Makefile | 1 +
src/backend/executor/execAsync.c | 152 +++++++++++
src/backend/executor/nodeAppend.c | 342 ++++++++++++++++++++----
src/backend/executor/nodeForeignscan.c | 21 ++
src/backend/nodes/bitmapset.c | 72 +++++
src/backend/nodes/copyfuncs.c | 3 +
src/backend/nodes/outfuncs.c | 3 +
src/backend/nodes/readfuncs.c | 3 +
src/backend/optimizer/path/allpaths.c | 24 ++
src/backend/optimizer/path/costsize.c | 40 ++-
src/backend/optimizer/plan/createplan.c | 41 ++-
src/backend/postmaster/pgstat.c | 3 +
src/backend/postmaster/syslogger.c | 2 +-
src/backend/utils/adt/ruleutils.c | 8 +-
src/backend/utils/resowner/resowner.c | 4 +-
src/include/executor/execAsync.h | 22 ++
src/include/executor/executor.h | 1 +
src/include/executor/nodeForeignscan.h | 3 +
src/include/foreign/fdwapi.h | 11 +
src/include/nodes/bitmapset.h | 1 +
src/include/nodes/execnodes.h | 23 +-
src/include/nodes/plannodes.h | 9 +
src/include/optimizer/paths.h | 2 +
src/include/pgstat.h | 3 +-
25 files changed, 740 insertions(+), 71 deletions(-)
create mode 100644 src/backend/executor/execAsync.c
create mode 100644 src/include/executor/execAsync.h
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 9092b4b309..d35de920c8 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -86,6 +86,7 @@ static void show_incremental_sort_keys(IncrementalSortState *incrsortstate,
List *ancestors, ExplainState *es);
static void show_merge_append_keys(MergeAppendState *mstate, List *ancestors,
ExplainState *es);
+static void show_append_info(AppendState *astate, ExplainState *es);
static void show_agg_keys(AggState *astate, List *ancestors,
ExplainState *es);
static void show_grouping_sets(PlanState *planstate, Agg *agg,
@@ -1389,6 +1390,8 @@ ExplainNode(PlanState *planstate, List *ancestors,
}
if (plan->parallel_aware)
appendStringInfoString(es->str, "Parallel ");
+ if (plan->async_capable)
+ appendStringInfoString(es->str, "Async ");
appendStringInfoString(es->str, pname);
es->indent++;
}
@@ -1969,6 +1972,11 @@ ExplainNode(PlanState *planstate, List *ancestors,
case T_Hash:
show_hash_info(castNode(HashState, planstate), es);
break;
+
+ case T_Append:
+ show_append_info(castNode(AppendState, planstate), es);
+ break;
+
default:
break;
}
@@ -2322,6 +2330,15 @@ show_merge_append_keys(MergeAppendState *mstate, List *ancestors,
ancestors, es);
}
+static void
+show_append_info(AppendState *astate, ExplainState *es)
+{
+ Append *plan = (Append *) astate->ps.plan;
+
+ if (plan->nasyncplans > 0)
+ ExplainPropertyInteger("Async subplans", "", plan->nasyncplans, es);
+}
+
/*
* Show the grouping keys for an Agg node.
*/
diff --git a/src/backend/executor/Makefile b/src/backend/executor/Makefile
index f990c6473a..1004647d4f 100644
--- a/src/backend/executor/Makefile
+++ b/src/backend/executor/Makefile
@@ -14,6 +14,7 @@ include $(top_builddir)/src/Makefile.global
OBJS = \
execAmi.o \
+ execAsync.o \
execCurrent.o \
execExpr.o \
execExprInterp.o \
diff --git a/src/backend/executor/execAsync.c b/src/backend/executor/execAsync.c
new file mode 100644
index 0000000000..2b7d1877e0
--- /dev/null
+++ b/src/backend/executor/execAsync.c
@@ -0,0 +1,152 @@
+/*-------------------------------------------------------------------------
+ *
+ * execAsync.c
+ * Support routines for asynchronous execution.
+ *
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ * src/backend/executor/execAsync.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "executor/execAsync.h"
+#include "executor/nodeAppend.h"
+#include "executor/nodeForeignscan.h"
+#include "miscadmin.h"
+#include "pgstat.h"
+#include "utils/memutils.h"
+#include "utils/resowner.h"
+
+/*
+ * ExecAsyncConfigureWait: Add wait event to the WaitEventSet if needed.
+ *
+ * If reinit is true, the caller didn't reuse existing WaitEventSet.
+ */
+bool
+ExecAsyncConfigureWait(WaitEventSet *wes, PlanState *node,
+ void *data, bool reinit)
+{
+ switch (nodeTag(node))
+ {
+ case T_ForeignScanState:
+ return ExecForeignAsyncConfigureWait((ForeignScanState *)node,
+ wes, data, reinit);
+ break;
+ default:
+ elog(ERROR, "unrecognized node type: %d",
+ (int) nodeTag(node));
+ }
+}
+
+/*
+ * struct for memory context callback argument used in ExecAsyncEventWait
+ */
+typedef struct {
+ int **p_refind;
+ int *p_refindsize;
+} ExecAsync_mcbarg;
+
+/*
+ * callback function to reset static variables pointing to the memory in
+ * TopTransactionContext in ExecAsyncEventWait.
+ */
+static void ExecAsyncMemoryContextCallback(void *arg)
+{
+ /* arg is the address of the variable refind in ExecAsyncEventWait */
+ ExecAsync_mcbarg *mcbarg = (ExecAsync_mcbarg *) arg;
+ *mcbarg->p_refind = NULL;
+ *mcbarg->p_refindsize = 0;
+}
+
+#define EVENT_BUFFER_SIZE 16
+
+/*
+ * ExecAsyncEventWait:
+ *
+ * Wait for async events to fire. Returns the Bitmapset of fired events.
+ */
+Bitmapset *
+ExecAsyncEventWait(PlanState **nodes, Bitmapset *waitnodes, long timeout)
+{
+ static int *refind = NULL;
+ static int refindsize = 0;
+ WaitEventSet *wes;
+ WaitEvent occurred_event[EVENT_BUFFER_SIZE];
+ int noccurred = 0;
+ Bitmapset *fired_events = NULL;
+ int i;
+ int n;
+
+ n = bms_num_members(waitnodes);
+ wes = CreateWaitEventSet(TopTransactionContext,
+ TopTransactionResourceOwner, n);
+ if (refindsize < n)
+ {
+ if (refindsize == 0)
+ refindsize = EVENT_BUFFER_SIZE; /* XXX */
+ while (refindsize < n)
+ refindsize *= 2;
+ if (refind)
+ refind = (int *) repalloc(refind, refindsize * sizeof(int));
+ else
+ {
+ static ExecAsync_mcbarg mcb_arg =
+ { &refind, &refindsize };
+ static MemoryContextCallback mcb =
+ { ExecAsyncMemoryContextCallback, (void *)&mcb_arg, NULL };
+ MemoryContext oldctxt =
+ MemoryContextSwitchTo(TopTransactionContext);
+
+ /*
+ * refind points to a memory block in
+ * TopTransactionContext. Register a callback to reset it.
+ */
+ MemoryContextRegisterResetCallback(TopTransactionContext, &mcb);
+ refind = (int *) palloc(refindsize * sizeof(int));
+ MemoryContextSwitchTo(oldctxt);
+ }
+ }
+
+ /* Prepare WaitEventSet for waiting on the waitnodes. */
+ n = 0;
+ for (i = bms_next_member(waitnodes, -1) ; i >= 0 ;
+ i = bms_next_member(waitnodes, i))
+ {
+ refind[i] = i;
+ if (ExecAsyncConfigureWait(wes, nodes[i], refind + i, true))
+ n++;
+ }
+
+ /* Return immediately if no node to wait. */
+ if (n == 0)
+ {
+ FreeWaitEventSet(wes);
+ return NULL;
+ }
+
+ noccurred = WaitEventSetWait(wes, timeout, occurred_event,
+ EVENT_BUFFER_SIZE,
+ WAIT_EVENT_ASYNC_WAIT);
+ FreeWaitEventSet(wes);
+ if (noccurred == 0)
+ return NULL;
+
+ for (i = 0 ; i < noccurred ; i++)
+ {
+ WaitEvent *w = &occurred_event[i];
+
+ if ((w->events & (WL_SOCKET_READABLE | WL_SOCKET_WRITEABLE)) != 0)
+ {
+ int n = *(int*)w->user_data;
+
+ fired_events = bms_add_member(fired_events, n);
+ }
+ }
+
+ return fired_events;
+}
diff --git a/src/backend/executor/nodeAppend.c b/src/backend/executor/nodeAppend.c
index 88919e62fa..60c36ee048 100644
--- a/src/backend/executor/nodeAppend.c
+++ b/src/backend/executor/nodeAppend.c
@@ -60,6 +60,7 @@
#include "executor/execdebug.h"
#include "executor/execPartition.h"
#include "executor/nodeAppend.h"
+#include "executor/execAsync.h"
#include "miscadmin.h"
/* Shared state for parallel-aware Append. */
@@ -80,6 +81,7 @@ struct ParallelAppendState
#define INVALID_SUBPLAN_INDEX -1
static TupleTableSlot *ExecAppend(PlanState *pstate);
+static TupleTableSlot *ExecAppendAsync(PlanState *pstate);
static bool choose_next_subplan_locally(AppendState *node);
static bool choose_next_subplan_for_leader(AppendState *node);
static bool choose_next_subplan_for_worker(AppendState *node);
@@ -103,22 +105,22 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
PlanState **appendplanstates;
Bitmapset *validsubplans;
int nplans;
+ int nasyncplans;
int firstvalid;
int i,
j;
/* check for unsupported flags */
- Assert(!(eflags & EXEC_FLAG_MARK));
+ Assert(!(eflags & (EXEC_FLAG_MARK | EXEC_FLAG_ASYNC)));
/*
* create new AppendState for our append node
*/
appendstate->ps.plan = (Plan *) node;
appendstate->ps.state = estate;
- appendstate->ps.ExecProcNode = ExecAppend;
/* Let choose_next_subplan_* function handle setting the first subplan */
- appendstate->as_whichplan = INVALID_SUBPLAN_INDEX;
+ appendstate->as_whichsyncplan = INVALID_SUBPLAN_INDEX;
/* If run-time partition pruning is enabled, then set that up now */
if (node->part_prune_info != NULL)
@@ -152,11 +154,12 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
/*
* When no run-time pruning is required and there's at least one
- * subplan, we can fill as_valid_subplans immediately, preventing
+ * subplan, we can fill as_valid_syncsubplans immediately, preventing
* later calls to ExecFindMatchingSubPlans.
*/
if (!prunestate->do_exec_prune && nplans > 0)
- appendstate->as_valid_subplans = bms_add_range(NULL, 0, nplans - 1);
+ appendstate->as_valid_syncsubplans =
+ bms_add_range(NULL, node->nasyncplans, nplans - 1);
}
else
{
@@ -167,8 +170,9 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
* subplans as valid; they must also all be initialized.
*/
Assert(nplans > 0);
- appendstate->as_valid_subplans = validsubplans =
- bms_add_range(NULL, 0, nplans - 1);
+ validsubplans = bms_add_range(NULL, 0, nplans - 1);
+ appendstate->as_valid_syncsubplans =
+ bms_add_range(NULL, node->nasyncplans, nplans - 1);
appendstate->as_prune_state = NULL;
}
@@ -192,10 +196,20 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
*/
j = 0;
firstvalid = nplans;
+ nasyncplans = 0;
+
i = -1;
while ((i = bms_next_member(validsubplans, i)) >= 0)
{
Plan *initNode = (Plan *) list_nth(node->appendplans, i);
+ int sub_eflags = eflags;
+
+ /* Let async-capable subplans run asynchronously */
+ if (i < node->nasyncplans)
+ {
+ sub_eflags |= EXEC_FLAG_ASYNC;
+ nasyncplans++;
+ }
/*
* Record the lowest appendplans index which is a valid partial plan.
@@ -203,13 +217,46 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
if (i >= node->first_partial_plan && j < firstvalid)
firstvalid = j;
- appendplanstates[j++] = ExecInitNode(initNode, estate, eflags);
+ appendplanstates[j++] = ExecInitNode(initNode, estate, sub_eflags);
}
appendstate->as_first_partial_plan = firstvalid;
appendstate->appendplans = appendplanstates;
appendstate->as_nplans = nplans;
+ /* fill in async stuff */
+ appendstate->as_nasyncplans = nasyncplans;
+ appendstate->as_syncdone = (nasyncplans == nplans);
+ appendstate->as_exec_prune = false;
+
+ /* choose appropriate version of Exec function */
+ if (appendstate->as_nasyncplans == 0)
+ appendstate->ps.ExecProcNode = ExecAppend;
+ else
+ appendstate->ps.ExecProcNode = ExecAppendAsync;
+
+ if (appendstate->as_nasyncplans)
+ {
+ appendstate->as_asyncresult = (TupleTableSlot **)
+ palloc0(appendstate->as_nasyncplans * sizeof(TupleTableSlot *));
+
+ /* initially, all async requests need a request */
+ appendstate->as_needrequest =
+ bms_add_range(NULL, 0, appendstate->as_nasyncplans - 1);
+
+ /*
+ * ExecAppendAsync needs as_valid_syncsubplans to handle async
+ * subnodes.
+ */
+ if (appendstate->as_prune_state != NULL &&
+ appendstate->as_prune_state->do_exec_prune)
+ {
+ Assert(appendstate->as_valid_syncsubplans == NULL);
+
+ appendstate->as_exec_prune = true;
+ }
+ }
+
/*
* Miscellaneous initialization
*/
@@ -233,7 +280,7 @@ ExecAppend(PlanState *pstate)
{
AppendState *node = castNode(AppendState, pstate);
- if (node->as_whichplan < 0)
+ if (node->as_whichsyncplan < 0)
{
/* Nothing to do if there are no subplans */
if (node->as_nplans == 0)
@@ -243,11 +290,13 @@ ExecAppend(PlanState *pstate)
* If no subplan has been chosen, we must choose one before
* proceeding.
*/
- if (node->as_whichplan == INVALID_SUBPLAN_INDEX &&
+ if (node->as_whichsyncplan == INVALID_SUBPLAN_INDEX &&
!node->choose_next_subplan(node))
return ExecClearTuple(node->ps.ps_ResultTupleSlot);
}
+ Assert(node->as_nasyncplans == 0);
+
for (;;)
{
PlanState *subnode;
@@ -258,8 +307,9 @@ ExecAppend(PlanState *pstate)
/*
* figure out which subplan we are currently processing
*/
- Assert(node->as_whichplan >= 0 && node->as_whichplan < node->as_nplans);
- subnode = node->appendplans[node->as_whichplan];
+ Assert(node->as_whichsyncplan >= 0 &&
+ node->as_whichsyncplan < node->as_nplans);
+ subnode = node->appendplans[node->as_whichsyncplan];
/*
* get a tuple from the subplan
@@ -282,6 +332,172 @@ ExecAppend(PlanState *pstate)
}
}
+static TupleTableSlot *
+ExecAppendAsync(PlanState *pstate)
+{
+ AppendState *node = castNode(AppendState, pstate);
+ Bitmapset *needrequest;
+ int i;
+
+ Assert(node->as_nasyncplans > 0);
+
+restart:
+ if (node->as_nasyncresult > 0)
+ {
+ --node->as_nasyncresult;
+ return node->as_asyncresult[node->as_nasyncresult];
+ }
+
+ if (node->as_exec_prune)
+ {
+ Bitmapset *valid_subplans =
+ ExecFindMatchingSubPlans(node->as_prune_state);
+
+ /* Distribute valid subplans into sync and async */
+ node->as_needrequest =
+ bms_intersect(node->as_needrequest, valid_subplans);
+ node->as_valid_syncsubplans =
+ bms_difference(valid_subplans, node->as_needrequest);
+
+ node->as_exec_prune = false;
+ }
+
+ needrequest = node->as_needrequest;
+ node->as_needrequest = NULL;
+ while ((i = bms_first_member(needrequest)) >= 0)
+ {
+ TupleTableSlot *slot;
+ PlanState *subnode = node->appendplans[i];
+
+ slot = ExecProcNode(subnode);
+ if (subnode->asyncstate == AS_AVAILABLE)
+ {
+ if (!TupIsNull(slot))
+ {
+ node->as_asyncresult[node->as_nasyncresult++] = slot;
+ node->as_needrequest = bms_add_member(node->as_needrequest, i);
+ }
+ }
+ else
+ node->as_pending_async = bms_add_member(node->as_pending_async, i);
+ }
+ bms_free(needrequest);
+
+ for (;;)
+ {
+ TupleTableSlot *result;
+
+ /* return now if a result is available */
+ if (node->as_nasyncresult > 0)
+ {
+ --node->as_nasyncresult;
+ return node->as_asyncresult[node->as_nasyncresult];
+ }
+
+ while (!bms_is_empty(node->as_pending_async))
+ {
+ /* Don't wait for async nodes if any sync node exists. */
+ long timeout = node->as_syncdone ? -1 : 0;
+ Bitmapset *fired;
+ int i;
+
+ fired = ExecAsyncEventWait(node->appendplans,
+ node->as_pending_async,
+ timeout);
+
+ if (bms_is_empty(fired) && node->as_syncdone)
+ {
+ /*
+ * We come here when all the subnodes had fired before
+ * waiting. Retry fetching from the nodes.
+ */
+ node->as_needrequest = node->as_pending_async;
+ node->as_pending_async = NULL;
+ goto restart;
+ }
+
+ while ((i = bms_first_member(fired)) >= 0)
+ {
+ TupleTableSlot *slot;
+ PlanState *subnode = node->appendplans[i];
+ slot = ExecProcNode(subnode);
+
+ Assert(subnode->asyncstate == AS_AVAILABLE);
+
+ if (!TupIsNull(slot))
+ {
+ node->as_asyncresult[node->as_nasyncresult++] = slot;
+ node->as_needrequest =
+ bms_add_member(node->as_needrequest, i);
+ }
+
+ node->as_pending_async =
+ bms_del_member(node->as_pending_async, i);
+ }
+ bms_free(fired);
+
+ /* return now if a result is available */
+ if (node->as_nasyncresult > 0)
+ {
+ --node->as_nasyncresult;
+ return node->as_asyncresult[node->as_nasyncresult];
+ }
+
+ if (!node->as_syncdone)
+ break;
+ }
+
+ /*
+ * If there is no asynchronous activity still pending and the
+ * synchronous activity is also complete, we're totally done scanning
+ * this node. Otherwise, we're done with the asynchronous stuff but
+ * must continue scanning the synchronous children.
+ */
+
+ if (!node->as_syncdone &&
+ node->as_whichsyncplan == INVALID_SUBPLAN_INDEX)
+ node->as_syncdone = !node->choose_next_subplan(node);
+
+ if (node->as_syncdone)
+ {
+ Assert(bms_is_empty(node->as_pending_async));
+ return ExecClearTuple(node->ps.ps_ResultTupleSlot);
+ }
+
+ /*
+ * get a tuple from the subplan
+ */
+ result = ExecProcNode(node->appendplans[node->as_whichsyncplan]);
+
+ if (!TupIsNull(result))
+ {
+ /*
+ * If the subplan gave us something then return it as-is. We do
+ * NOT make use of the result slot that was set up in
+ * ExecInitAppend; there's no need for it.
+ */
+ return result;
+ }
+
+ /*
+ * Go on to the "next" subplan. If no more subplans, return the empty
+ * slot set up for us by ExecInitAppend, unless there are async plans
+ * we have yet to finish.
+ */
+ if (!node->choose_next_subplan(node))
+ {
+ node->as_syncdone = true;
+ if (bms_is_empty(node->as_pending_async))
+ {
+ Assert(bms_is_empty(node->as_needrequest));
+ return ExecClearTuple(node->ps.ps_ResultTupleSlot);
+ }
+ }
+
+ /* Else loop back and try to get a tuple from the new subplan */
+ }
+}
+
/* ----------------------------------------------------------------
* ExecEndAppend
*
@@ -324,10 +540,18 @@ ExecReScanAppend(AppendState *node)
bms_overlap(node->ps.chgParam,
node->as_prune_state->execparamids))
{
- bms_free(node->as_valid_subplans);
- node->as_valid_subplans = NULL;
+ bms_free(node->as_valid_syncsubplans);
+ node->as_valid_syncsubplans = NULL;
}
+ /* Reset async state. */
+ for (i = 0; i < node->as_nasyncplans; ++i)
+ ExecShutdownNode(node->appendplans[i]);
+
+ node->as_nasyncresult = 0;
+ node->as_needrequest = bms_add_range(NULL, 0, node->as_nasyncplans - 1);
+ node->as_syncdone = (node->as_nasyncplans == node->as_nplans);
+
for (i = 0; i < node->as_nplans; i++)
{
PlanState *subnode = node->appendplans[i];
@@ -348,7 +572,7 @@ ExecReScanAppend(AppendState *node)
}
/* Let choose_next_subplan_* function handle setting the first subplan */
- node->as_whichplan = INVALID_SUBPLAN_INDEX;
+ node->as_whichsyncplan = INVALID_SUBPLAN_INDEX;
}
/* ----------------------------------------------------------------
@@ -436,7 +660,7 @@ ExecAppendInitializeWorker(AppendState *node, ParallelWorkerContext *pwcxt)
static bool
choose_next_subplan_locally(AppendState *node)
{
- int whichplan = node->as_whichplan;
+ int whichplan = node->as_whichsyncplan;
int nextplan;
/* We should never be called when there are no subplans */
@@ -451,10 +675,18 @@ choose_next_subplan_locally(AppendState *node)
*/
if (whichplan == INVALID_SUBPLAN_INDEX)
{
- if (node->as_valid_subplans == NULL)
- node->as_valid_subplans =
+ /* Shouldn't have an active async node */
+ Assert(bms_is_empty(node->as_needrequest));
+
+ if (node->as_valid_syncsubplans == NULL)
+ node->as_valid_syncsubplans =
ExecFindMatchingSubPlans(node->as_prune_state);
+ /* Exclude async plans */
+ if (node->as_nasyncplans > 0)
+ bms_del_range(node->as_valid_syncsubplans,
+ 0, node->as_nasyncplans - 1);
+
whichplan = -1;
}
@@ -462,14 +694,14 @@ choose_next_subplan_locally(AppendState *node)
Assert(whichplan >= -1 && whichplan <= node->as_nplans);
if (ScanDirectionIsForward(node->ps.state->es_direction))
- nextplan = bms_next_member(node->as_valid_subplans, whichplan);
+ nextplan = bms_next_member(node->as_valid_syncsubplans, whichplan);
else
- nextplan = bms_prev_member(node->as_valid_subplans, whichplan);
+ nextplan = bms_prev_member(node->as_valid_syncsubplans, whichplan);
if (nextplan < 0)
return false;
- node->as_whichplan = nextplan;
+ node->as_whichsyncplan = nextplan;
return true;
}
@@ -490,29 +722,29 @@ choose_next_subplan_for_leader(AppendState *node)
/* Backward scan is not supported by parallel-aware plans */
Assert(ScanDirectionIsForward(node->ps.state->es_direction));
- /* We should never be called when there are no subplans */
- Assert(node->as_nplans > 0);
+ /* We should never be called when there are no sync subplans */
+ Assert(node->as_nplans > node->as_nasyncplans);
LWLockAcquire(&pstate->pa_lock, LW_EXCLUSIVE);
- if (node->as_whichplan != INVALID_SUBPLAN_INDEX)
+ if (node->as_whichsyncplan != INVALID_SUBPLAN_INDEX)
{
/* Mark just-completed subplan as finished. */
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
}
else
{
/* Start with last subplan. */
- node->as_whichplan = node->as_nplans - 1;
+ node->as_whichsyncplan = node->as_nplans - 1;
/*
* If we've yet to determine the valid subplans then do so now. If
* run-time pruning is disabled then the valid subplans will always be
* set to all subplans.
*/
- if (node->as_valid_subplans == NULL)
+ if (node->as_valid_syncsubplans == NULL)
{
- node->as_valid_subplans =
+ node->as_valid_syncsubplans =
ExecFindMatchingSubPlans(node->as_prune_state);
/*
@@ -524,26 +756,26 @@ choose_next_subplan_for_leader(AppendState *node)
}
/* Loop until we find a subplan to execute. */
- while (pstate->pa_finished[node->as_whichplan])
+ while (pstate->pa_finished[node->as_whichsyncplan])
{
- if (node->as_whichplan == 0)
+ if (node->as_whichsyncplan == 0)
{
pstate->pa_next_plan = INVALID_SUBPLAN_INDEX;
- node->as_whichplan = INVALID_SUBPLAN_INDEX;
+ node->as_whichsyncplan = INVALID_SUBPLAN_INDEX;
LWLockRelease(&pstate->pa_lock);
return false;
}
/*
- * We needn't pay attention to as_valid_subplans here as all invalid
+ * We needn't pay attention to as_valid_syncsubplans here as all invalid
* plans have been marked as finished.
*/
- node->as_whichplan--;
+ node->as_whichsyncplan--;
}
/* If non-partial, immediately mark as finished. */
- if (node->as_whichplan < node->as_first_partial_plan)
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ if (node->as_whichsyncplan < node->as_first_partial_plan)
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
LWLockRelease(&pstate->pa_lock);
@@ -571,23 +803,23 @@ choose_next_subplan_for_worker(AppendState *node)
/* Backward scan is not supported by parallel-aware plans */
Assert(ScanDirectionIsForward(node->ps.state->es_direction));
- /* We should never be called when there are no subplans */
- Assert(node->as_nplans > 0);
+ /* We should never be called when there are no sync subplans */
+ Assert(node->as_nplans > node->as_nasyncplans);
LWLockAcquire(&pstate->pa_lock, LW_EXCLUSIVE);
/* Mark just-completed subplan as finished. */
- if (node->as_whichplan != INVALID_SUBPLAN_INDEX)
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ if (node->as_whichsyncplan != INVALID_SUBPLAN_INDEX)
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
/*
* If we've yet to determine the valid subplans then do so now. If
* run-time pruning is disabled then the valid subplans will always be set
* to all subplans.
*/
- else if (node->as_valid_subplans == NULL)
+ else if (node->as_valid_syncsubplans == NULL)
{
- node->as_valid_subplans =
+ node->as_valid_syncsubplans =
ExecFindMatchingSubPlans(node->as_prune_state);
mark_invalid_subplans_as_finished(node);
}
@@ -600,30 +832,30 @@ choose_next_subplan_for_worker(AppendState *node)
}
/* Save the plan from which we are starting the search. */
- node->as_whichplan = pstate->pa_next_plan;
+ node->as_whichsyncplan = pstate->pa_next_plan;
/* Loop until we find a valid subplan to execute. */
while (pstate->pa_finished[pstate->pa_next_plan])
{
int nextplan;
- nextplan = bms_next_member(node->as_valid_subplans,
+ nextplan = bms_next_member(node->as_valid_syncsubplans,
pstate->pa_next_plan);
if (nextplan >= 0)
{
/* Advance to the next valid plan. */
pstate->pa_next_plan = nextplan;
}
- else if (node->as_whichplan > node->as_first_partial_plan)
+ else if (node->as_whichsyncplan > node->as_first_partial_plan)
{
/*
* Try looping back to the first valid partial plan, if there is
* one. If there isn't, arrange to bail out below.
*/
- nextplan = bms_next_member(node->as_valid_subplans,
+ nextplan = bms_next_member(node->as_valid_syncsubplans,
node->as_first_partial_plan - 1);
pstate->pa_next_plan =
- nextplan < 0 ? node->as_whichplan : nextplan;
+ nextplan < 0 ? node->as_whichsyncplan : nextplan;
}
else
{
@@ -631,10 +863,10 @@ choose_next_subplan_for_worker(AppendState *node)
* At last plan, and either there are no partial plans or we've
* tried them all. Arrange to bail out.
*/
- pstate->pa_next_plan = node->as_whichplan;
+ pstate->pa_next_plan = node->as_whichsyncplan;
}
- if (pstate->pa_next_plan == node->as_whichplan)
+ if (pstate->pa_next_plan == node->as_whichsyncplan)
{
/* We've tried everything! */
pstate->pa_next_plan = INVALID_SUBPLAN_INDEX;
@@ -644,8 +876,8 @@ choose_next_subplan_for_worker(AppendState *node)
}
/* Pick the plan we found, and advance pa_next_plan one more time. */
- node->as_whichplan = pstate->pa_next_plan;
- pstate->pa_next_plan = bms_next_member(node->as_valid_subplans,
+ node->as_whichsyncplan = pstate->pa_next_plan;
+ pstate->pa_next_plan = bms_next_member(node->as_valid_syncsubplans,
pstate->pa_next_plan);
/*
@@ -654,7 +886,7 @@ choose_next_subplan_for_worker(AppendState *node)
*/
if (pstate->pa_next_plan < 0)
{
- int nextplan = bms_next_member(node->as_valid_subplans,
+ int nextplan = bms_next_member(node->as_valid_syncsubplans,
node->as_first_partial_plan - 1);
if (nextplan >= 0)
@@ -671,8 +903,8 @@ choose_next_subplan_for_worker(AppendState *node)
}
/* If non-partial, immediately mark as finished. */
- if (node->as_whichplan < node->as_first_partial_plan)
- node->as_pstate->pa_finished[node->as_whichplan] = true;
+ if (node->as_whichsyncplan < node->as_first_partial_plan)
+ node->as_pstate->pa_finished[node->as_whichsyncplan] = true;
LWLockRelease(&pstate->pa_lock);
@@ -699,13 +931,13 @@ mark_invalid_subplans_as_finished(AppendState *node)
Assert(node->as_prune_state);
/* Nothing to do if all plans are valid */
- if (bms_num_members(node->as_valid_subplans) == node->as_nplans)
+ if (bms_num_members(node->as_valid_syncsubplans) == node->as_nplans)
return;
/* Mark all non-valid plans as finished */
for (i = 0; i < node->as_nplans; i++)
{
- if (!bms_is_member(i, node->as_valid_subplans))
+ if (!bms_is_member(i, node->as_valid_syncsubplans))
node->as_pstate->pa_finished[i] = true;
}
}
diff --git a/src/backend/executor/nodeForeignscan.c b/src/backend/executor/nodeForeignscan.c
index 513471ab9b..3bf4aaa63d 100644
--- a/src/backend/executor/nodeForeignscan.c
+++ b/src/backend/executor/nodeForeignscan.c
@@ -141,6 +141,10 @@ ExecInitForeignScan(ForeignScan *node, EState *estate, int eflags)
scanstate->ss.ps.plan = (Plan *) node;
scanstate->ss.ps.state = estate;
scanstate->ss.ps.ExecProcNode = ExecForeignScan;
+ scanstate->ss.ps.asyncstate = AS_AVAILABLE;
+
+ if ((eflags & EXEC_FLAG_ASYNC) != 0)
+ scanstate->fs_async = true;
/*
* Miscellaneous initialization
@@ -384,3 +388,20 @@ ExecShutdownForeignScan(ForeignScanState *node)
if (fdwroutine->ShutdownForeignScan)
fdwroutine->ShutdownForeignScan(node);
}
+
+/* ----------------------------------------------------------------
+ * ExecAsyncForeignScanConfigureWait
+ *
+ * In async mode, configure for a wait
+ * ----------------------------------------------------------------
+ */
+bool
+ExecForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes,
+ void *caller_data, bool reinit)
+{
+ FdwRoutine *fdwroutine = node->fdwroutine;
+
+ Assert(fdwroutine->ForeignAsyncConfigureWait != NULL);
+ return fdwroutine->ForeignAsyncConfigureWait(node, wes,
+ caller_data, reinit);
+}
diff --git a/src/backend/nodes/bitmapset.c b/src/backend/nodes/bitmapset.c
index 2719ea45a3..05b625783b 100644
--- a/src/backend/nodes/bitmapset.c
+++ b/src/backend/nodes/bitmapset.c
@@ -895,6 +895,78 @@ bms_add_range(Bitmapset *a, int lower, int upper)
return a;
}
+/*
+ * bms_del_range
+ * Delete members in the range of 'lower' to 'upper' from the set.
+ *
+ * Note this could also be done by calling bms_del_member in a loop, however,
+ * using this function will be faster when the range is large as we work at
+ * the bitmapword level rather than at bit level.
+ */
+Bitmapset *
+bms_del_range(Bitmapset *a, int lower, int upper)
+{
+ int lwordnum,
+ lbitnum,
+ uwordnum,
+ ushiftbits,
+ wordnum;
+
+ if (lower < 0 || upper < 0)
+ elog(ERROR, "negative bitmapset member not allowed");
+ if (lower > upper)
+ elog(ERROR, "lower range must not be above upper range");
+ uwordnum = WORDNUM(upper);
+
+ if (a == NULL)
+ {
+ a = (Bitmapset *) palloc0(BITMAPSET_SIZE(uwordnum + 1));
+ a->nwords = uwordnum + 1;
+ }
+
+ /* ensure we have enough words to store the upper bit */
+ else if (uwordnum >= a->nwords)
+ {
+ int oldnwords = a->nwords;
+ int i;
+
+ a = (Bitmapset *) repalloc(a, BITMAPSET_SIZE(uwordnum + 1));
+ a->nwords = uwordnum + 1;
+ /* zero out the enlarged portion */
+ for (i = oldnwords; i < a->nwords; i++)
+ a->words[i] = 0;
+ }
+
+ wordnum = lwordnum = WORDNUM(lower);
+
+ lbitnum = BITNUM(lower);
+ ushiftbits = BITNUM(upper) + 1;
+
+ /*
+ * Special case when lwordnum is the same as uwordnum we must perform the
+ * upper and lower masking on the word.
+ */
+ if (lwordnum == uwordnum)
+ {
+ a->words[lwordnum] &= ((bitmapword) (((bitmapword) 1 << lbitnum) - 1)
+ | (~(bitmapword) 0) << ushiftbits);
+ }
+ else
+ {
+ /* turn off lbitnum and all bits left of it */
+ a->words[wordnum++] &= (bitmapword) (((bitmapword) 1 << lbitnum) - 1);
+
+ /* turn off all bits for any intermediate words */
+ while (wordnum < uwordnum)
+ a->words[wordnum++] = (bitmapword) 0;
+
+ /* turn off upper's bit and all bits right of it. */
+ a->words[uwordnum] &= (~(bitmapword) 0) << ushiftbits;
+ }
+
+ return a;
+}
+
/*
* bms_int_members - like bms_intersect, but left input is recycled
*/
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index d8cf87e6d0..89a49e2fdc 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -121,6 +121,7 @@ CopyPlanFields(const Plan *from, Plan *newnode)
COPY_SCALAR_FIELD(plan_width);
COPY_SCALAR_FIELD(parallel_aware);
COPY_SCALAR_FIELD(parallel_safe);
+ COPY_SCALAR_FIELD(async_capable);
COPY_SCALAR_FIELD(plan_node_id);
COPY_NODE_FIELD(targetlist);
COPY_NODE_FIELD(qual);
@@ -246,6 +247,8 @@ _copyAppend(const Append *from)
COPY_NODE_FIELD(appendplans);
COPY_SCALAR_FIELD(first_partial_plan);
COPY_NODE_FIELD(part_prune_info);
+ COPY_SCALAR_FIELD(nasyncplans);
+ COPY_SCALAR_FIELD(referent);
return newnode;
}
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index e2f177515d..d4bb44b268 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -334,6 +334,7 @@ _outPlanInfo(StringInfo str, const Plan *node)
WRITE_INT_FIELD(plan_width);
WRITE_BOOL_FIELD(parallel_aware);
WRITE_BOOL_FIELD(parallel_safe);
+ WRITE_BOOL_FIELD(async_capable);
WRITE_INT_FIELD(plan_node_id);
WRITE_NODE_FIELD(targetlist);
WRITE_NODE_FIELD(qual);
@@ -436,6 +437,8 @@ _outAppend(StringInfo str, const Append *node)
WRITE_NODE_FIELD(appendplans);
WRITE_INT_FIELD(first_partial_plan);
WRITE_NODE_FIELD(part_prune_info);
+ WRITE_INT_FIELD(nasyncplans);
+ WRITE_INT_FIELD(referent);
}
static void
diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index 42050ab719..63af7c02d8 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -1572,6 +1572,7 @@ ReadCommonPlan(Plan *local_node)
READ_INT_FIELD(plan_width);
READ_BOOL_FIELD(parallel_aware);
READ_BOOL_FIELD(parallel_safe);
+ READ_BOOL_FIELD(async_capable);
READ_INT_FIELD(plan_node_id);
READ_NODE_FIELD(targetlist);
READ_NODE_FIELD(qual);
@@ -1672,6 +1673,8 @@ _readAppend(void)
READ_NODE_FIELD(appendplans);
READ_INT_FIELD(first_partial_plan);
READ_NODE_FIELD(part_prune_info);
+ READ_INT_FIELD(nasyncplans);
+ READ_INT_FIELD(referent);
READ_DONE();
}
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index d984da25d7..bb4c8723bc 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -3937,6 +3937,30 @@ generate_partitionwise_join_paths(PlannerInfo *root, RelOptInfo *rel)
list_free(live_children);
}
+/*
+ * is_projection_capable_path
+ * Check whether a given Path node is async-capable.
+ */
+bool
+is_async_capable_path(Path *path)
+{
+ switch (nodeTag(path))
+ {
+ case T_ForeignPath:
+ {
+ FdwRoutine *fdwroutine = path->parent->fdwroutine;
+
+ Assert(fdwroutine != NULL);
+ if (fdwroutine->IsForeignPathAsyncCapable != NULL &&
+ fdwroutine->IsForeignPathAsyncCapable((ForeignPath *) path))
+ return true;
+ }
+ default:
+ break;
+ }
+ return false;
+}
+
/*****************************************************************************
* DEBUG SUPPORT
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index b976afb69d..c4c83b5887 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -2050,13 +2050,9 @@ cost_append(AppendPath *apath)
if (pathkeys == NIL)
{
- Path *subpath = (Path *) linitial(apath->subpaths);
+ Cost async_min_startup_cost = -1.0;
- /*
- * For an unordered, non-parallel-aware Append we take the startup
- * cost as the startup cost of the first subpath.
- */
- apath->path.startup_cost = subpath->startup_cost;
+ apath->path.startup_cost = -1.0;
/* Compute rows and costs as sums of subplan rows and costs. */
foreach(l, apath->subpaths)
@@ -2065,6 +2061,38 @@ cost_append(AppendPath *apath)
apath->path.rows += subpath->rows;
apath->path.total_cost += subpath->total_cost;
+
+ if (!is_async_capable_path(subpath))
+ {
+ /*
+ * For an unordered, non-parallel-aware Append we take the
+ * startup cost as the startup cost of the first subpath.
+ */
+ if (apath->path.startup_cost < 0)
+ apath->path.startup_cost = subpath->startup_cost;
+ }
+ else if (apath->path.startup_cost < 0)
+ {
+ /*
+ * Usually async-capable paths don't affect the startup
+ * cost of Append. However, if no sync paths are
+ * contained, the startup cost of the Append is the minimal
+ * async startup cost. Remember the cost just in case.
+ */
+ if (async_min_startup_cost < 0 ||
+ async_min_startup_cost > subpath->startup_cost)
+ async_min_startup_cost = subpath->startup_cost;
+ }
+ }
+
+ /*
+ * Use the minimum async startup cost if no sync startup has been
+ * found.
+ */
+ if (apath->path.startup_cost < 0)
+ {
+ Assert(async_min_startup_cost >= 0);
+ apath->path.startup_cost = async_min_startup_cost;
}
}
else
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index eb9543f6ad..7f75708134 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -1082,6 +1082,11 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
bool tlist_was_changed = false;
List *pathkeys = best_path->path.pathkeys;
List *subplans = NIL;
+ List *asyncplans = NIL;
+ List *syncplans = NIL;
+ List *asyncpaths = NIL;
+ List *syncpaths = NIL;
+ List *newsubpaths = NIL;
ListCell *subpaths;
RelOptInfo *rel = best_path->path.parent;
PartitionPruneInfo *partpruneinfo = NULL;
@@ -1090,6 +1095,9 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
Oid *nodeSortOperators = NULL;
Oid *nodeCollations = NULL;
bool *nodeNullsFirst = NULL;
+ int nasyncplans = 0;
+ bool first = true;
+ bool referent_is_sync = true;
/*
* The subpaths list could be empty, if every child was proven empty by
@@ -1219,9 +1227,36 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
}
}
- subplans = lappend(subplans, subplan);
+ /*
+ * Classify as async-capable or not. If we have decided to run the
+ * children in parallel, we cannot any one of them run asynchronously.
+ */
+ if (!best_path->path.parallel_safe && is_async_capable_path(subpath))
+ {
+ subplan->async_capable = true;
+ asyncplans = lappend(asyncplans, subplan);
+ asyncpaths = lappend(asyncpaths, subpath);
+ ++nasyncplans;
+ if (first)
+ referent_is_sync = false;
+ }
+ else
+ {
+ syncplans = lappend(syncplans, subplan);
+ syncpaths = lappend(syncpaths, subpath);
+ }
+
+ first = false;
}
+ /*
+ * subplan contains asyncplans in the first half, if any, and sync plans in
+ * another half, if any. We need that the same for subpaths to make
+ * partition pruning information in sync with subplans.
+ */
+ subplans = list_concat(asyncplans, syncplans);
+ newsubpaths = list_concat(asyncpaths, syncpaths);
+
/*
* If any quals exist, they may be useful to perform further partition
* pruning during execution. Gather information needed by the executor to
@@ -1249,7 +1284,7 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
if (prunequal != NIL)
partpruneinfo =
make_partition_pruneinfo(root, rel,
- best_path->subpaths,
+ newsubpaths,
best_path->partitioned_rels,
prunequal);
}
@@ -1257,6 +1292,8 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
plan->appendplans = subplans;
plan->first_partial_plan = best_path->first_partial_path;
plan->part_prune_info = partpruneinfo;
+ plan->nasyncplans = nasyncplans;
+ plan->referent = referent_is_sync ? nasyncplans : 0;
copy_generic_path_info(&plan->plan, (Path *) best_path);
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 309378ae54..d9ea75d823 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -3882,6 +3882,9 @@ pgstat_get_wait_ipc(WaitEventIPC w)
case WAIT_EVENT_XACT_GROUP_UPDATE:
event_name = "XactGroupUpdate";
break;
+ case WAIT_EVENT_ASYNC_WAIT:
+ event_name = "AsyncExecWait";
+ break;
/* no default case, so that compiler will warn */
}
diff --git a/src/backend/postmaster/syslogger.c b/src/backend/postmaster/syslogger.c
index ffcb54968f..a4de6d90e2 100644
--- a/src/backend/postmaster/syslogger.c
+++ b/src/backend/postmaster/syslogger.c
@@ -300,7 +300,7 @@ SysLoggerMain(int argc, char *argv[])
* syslog pipe, which implies that all other backends have exited
* (including the postmaster).
*/
- wes = CreateWaitEventSet(CurrentMemoryContext, 2);
+ wes = CreateWaitEventSet(CurrentMemoryContext, NULL, 2);
AddWaitEventToSet(wes, WL_LATCH_SET, PGINVALID_SOCKET, MyLatch, NULL);
#ifndef WIN32
AddWaitEventToSet(wes, WL_SOCKET_READABLE, syslogPipe[0], NULL, NULL);
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 076c3c019f..f7b5587d7f 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -4584,10 +4584,14 @@ set_deparse_plan(deparse_namespace *dpns, Plan *plan)
* tlists according to one of the children, and the first one is the most
* natural choice. Likewise special-case ModifyTable to pretend that the
* first child plan is the OUTER referent; this is to support RETURNING
- * lists containing references to non-target relations.
+ * lists containing references to non-target relations. For Append, use the
+ * explicitly specified referent.
*/
if (IsA(plan, Append))
- dpns->outer_plan = linitial(((Append *) plan)->appendplans);
+ {
+ Append *app = (Append *) plan;
+ dpns->outer_plan = list_nth(app->appendplans, app->referent);
+ }
else if (IsA(plan, MergeAppend))
dpns->outer_plan = linitial(((MergeAppend *) plan)->mergeplans);
else if (IsA(plan, ModifyTable))
diff --git a/src/backend/utils/resowner/resowner.c b/src/backend/utils/resowner/resowner.c
index 237ca9fa30..27742a1641 100644
--- a/src/backend/utils/resowner/resowner.c
+++ b/src/backend/utils/resowner/resowner.c
@@ -1416,7 +1416,7 @@ void
ResourceOwnerForgetWES(ResourceOwner owner, WaitEventSet *events)
{
/*
- * XXXX: There's no property to show as an identier of a wait event set,
+ * XXXX: There's no property to show as an identifier of a wait event set,
* use its pointer instead.
*/
if (!ResourceArrayRemove(&(owner->wesarr), PointerGetDatum(events)))
@@ -1431,7 +1431,7 @@ static void
PrintWESLeakWarning(WaitEventSet *events)
{
/*
- * XXXX: There's no property to show as an identier of a wait event set,
+ * XXXX: There's no property to show as an identifier of a wait event set,
* use its pointer instead.
*/
elog(WARNING, "wait event set leak: %p still referenced",
diff --git a/src/include/executor/execAsync.h b/src/include/executor/execAsync.h
new file mode 100644
index 0000000000..3b6bf4a516
--- /dev/null
+++ b/src/include/executor/execAsync.h
@@ -0,0 +1,22 @@
+/*--------------------------------------------------------------------
+ * execAsync.c
+ * Support functions for asynchronous query execution
+ *
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ * src/backend/executor/execAsync.c
+ *--------------------------------------------------------------------
+ */
+#ifndef EXECASYNC_H
+#define EXECASYNC_H
+
+#include "nodes/execnodes.h"
+#include "storage/latch.h"
+
+extern bool ExecAsyncConfigureWait(WaitEventSet *wes, PlanState *node,
+ void *data, bool reinit);
+extern Bitmapset *ExecAsyncEventWait(PlanState **nodes, Bitmapset *waitnodes,
+ long timeout);
+#endif /* EXECASYNC_H */
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index c7deeac662..aca9e2bddd 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -59,6 +59,7 @@
#define EXEC_FLAG_MARK 0x0008 /* need mark/restore */
#define EXEC_FLAG_SKIP_TRIGGERS 0x0010 /* skip AfterTrigger calls */
#define EXEC_FLAG_WITH_NO_DATA 0x0020 /* rel scannability doesn't matter */
+#define EXEC_FLAG_ASYNC 0x0040 /* request async execution */
/* Hook for plugins to get control in ExecutorStart() */
diff --git a/src/include/executor/nodeForeignscan.h b/src/include/executor/nodeForeignscan.h
index 326d713ebf..71a233b41f 100644
--- a/src/include/executor/nodeForeignscan.h
+++ b/src/include/executor/nodeForeignscan.h
@@ -30,5 +30,8 @@ extern void ExecForeignScanReInitializeDSM(ForeignScanState *node,
extern void ExecForeignScanInitializeWorker(ForeignScanState *node,
ParallelWorkerContext *pwcxt);
extern void ExecShutdownForeignScan(ForeignScanState *node);
+extern bool ExecForeignAsyncConfigureWait(ForeignScanState *node,
+ WaitEventSet *wes,
+ void *caller_data, bool reinit);
#endif /* NODEFOREIGNSCAN_H */
diff --git a/src/include/foreign/fdwapi.h b/src/include/foreign/fdwapi.h
index 95556dfb15..853ba2b5ad 100644
--- a/src/include/foreign/fdwapi.h
+++ b/src/include/foreign/fdwapi.h
@@ -169,6 +169,11 @@ typedef bool (*IsForeignScanParallelSafe_function) (PlannerInfo *root,
typedef List *(*ReparameterizeForeignPathByChild_function) (PlannerInfo *root,
List *fdw_private,
RelOptInfo *child_rel);
+typedef bool (*IsForeignPathAsyncCapable_function) (ForeignPath *path);
+typedef bool (*ForeignAsyncConfigureWait_function) (ForeignScanState *node,
+ WaitEventSet *wes,
+ void *caller_data,
+ bool reinit);
/*
* FdwRoutine is the struct returned by a foreign-data wrapper's handler
@@ -190,6 +195,7 @@ typedef struct FdwRoutine
GetForeignPlan_function GetForeignPlan;
BeginForeignScan_function BeginForeignScan;
IterateForeignScan_function IterateForeignScan;
+ IterateForeignScan_function IterateForeignScanAsync;
ReScanForeignScan_function ReScanForeignScan;
EndForeignScan_function EndForeignScan;
@@ -242,6 +248,11 @@ typedef struct FdwRoutine
InitializeDSMForeignScan_function InitializeDSMForeignScan;
ReInitializeDSMForeignScan_function ReInitializeDSMForeignScan;
InitializeWorkerForeignScan_function InitializeWorkerForeignScan;
+
+ /* Support functions for asynchronous execution */
+ IsForeignPathAsyncCapable_function IsForeignPathAsyncCapable;
+ ForeignAsyncConfigureWait_function ForeignAsyncConfigureWait;
+
ShutdownForeignScan_function ShutdownForeignScan;
/* Support functions for path reparameterization. */
diff --git a/src/include/nodes/bitmapset.h b/src/include/nodes/bitmapset.h
index d113c271ee..177e6218cb 100644
--- a/src/include/nodes/bitmapset.h
+++ b/src/include/nodes/bitmapset.h
@@ -107,6 +107,7 @@ extern Bitmapset *bms_add_members(Bitmapset *a, const Bitmapset *b);
extern Bitmapset *bms_add_range(Bitmapset *a, int lower, int upper);
extern Bitmapset *bms_int_members(Bitmapset *a, const Bitmapset *b);
extern Bitmapset *bms_del_members(Bitmapset *a, const Bitmapset *b);
+extern Bitmapset *bms_del_range(Bitmapset *a, int lower, int upper);
extern Bitmapset *bms_join(Bitmapset *a, Bitmapset *b);
/* support for iterating through the integer elements of a set: */
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 98e0072b8a..cd50494c74 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -938,6 +938,12 @@ typedef TupleTableSlot *(*ExecProcNodeMtd) (struct PlanState *pstate);
* abstract superclass for all PlanState-type nodes.
* ----------------
*/
+typedef enum AsyncState
+{
+ AS_AVAILABLE,
+ AS_WAITING
+} AsyncState;
+
typedef struct PlanState
{
NodeTag type;
@@ -1026,6 +1032,11 @@ typedef struct PlanState
bool outeropsset;
bool inneropsset;
bool resultopsset;
+
+ /* Async subnode execution stuff */
+ AsyncState asyncstate;
+
+ int32 padding; /* to keep alignment of derived types */
} PlanState;
/* ----------------
@@ -1221,14 +1232,21 @@ struct AppendState
PlanState ps; /* its first field is NodeTag */
PlanState **appendplans; /* array of PlanStates for my inputs */
int as_nplans;
- int as_whichplan;
+ int as_whichsyncplan; /* which sync plan is being executed */
int as_first_partial_plan; /* Index of 'appendplans' containing
* the first partial plan */
+ int as_nasyncplans; /* # of async-capable children */
ParallelAppendState *as_pstate; /* parallel coordination info */
Size pstate_len; /* size of parallel coordination info */
struct PartitionPruneState *as_prune_state;
- Bitmapset *as_valid_subplans;
+ Bitmapset *as_valid_syncsubplans;
bool (*choose_next_subplan) (AppendState *);
+ bool as_syncdone; /* all synchronous plans done? */
+ Bitmapset *as_needrequest; /* async plans needing a new request */
+ Bitmapset *as_pending_async; /* pending async plans */
+ TupleTableSlot **as_asyncresult; /* results of each async plan */
+ int as_nasyncresult; /* # of valid entries in as_asyncresult */
+ bool as_exec_prune; /* runtime pruning needed for async exec? */
};
/* ----------------
@@ -1796,6 +1814,7 @@ typedef struct ForeignScanState
Size pscan_len; /* size of parallel coordination information */
/* use struct pointer to avoid including fdwapi.h here */
struct FdwRoutine *fdwroutine;
+ bool fs_async;
void *fdw_state; /* foreign-data wrapper can keep state here */
} ForeignScanState;
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
index 83e01074ed..abad89b327 100644
--- a/src/include/nodes/plannodes.h
+++ b/src/include/nodes/plannodes.h
@@ -135,6 +135,11 @@ typedef struct Plan
bool parallel_aware; /* engage parallel-aware logic? */
bool parallel_safe; /* OK to use as part of parallel plan? */
+ /*
+ * information needed for asynchronous execution
+ */
+ bool async_capable; /* engage asynchronous execution logic? */
+
/*
* Common structural data for all Plan types.
*/
@@ -262,6 +267,10 @@ typedef struct Append
/* Info for run-time subplan pruning; NULL if we're not doing that */
struct PartitionPruneInfo *part_prune_info;
+
+ /* Async child node execution stuff */
+ int nasyncplans; /* # async subplans, always at start of list */
+ int referent; /* index of inheritance tree referent */
} Append;
/* ----------------
diff --git a/src/include/optimizer/paths.h b/src/include/optimizer/paths.h
index 10b6e81079..53876b2d8b 100644
--- a/src/include/optimizer/paths.h
+++ b/src/include/optimizer/paths.h
@@ -241,4 +241,6 @@ extern PathKey *make_canonical_pathkey(PlannerInfo *root,
extern void add_paths_to_append_rel(PlannerInfo *root, RelOptInfo *rel,
List *live_childrels);
+extern bool is_async_capable_path(Path *path);
+
#endif /* PATHS_H */
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index c55dc1481c..2259910637 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -887,7 +887,8 @@ typedef enum
WAIT_EVENT_REPLICATION_SLOT_DROP,
WAIT_EVENT_SAFE_SNAPSHOT,
WAIT_EVENT_SYNC_REP,
- WAIT_EVENT_XACT_GROUP_UPDATE
+ WAIT_EVENT_XACT_GROUP_UPDATE,
+ WAIT_EVENT_ASYNC_WAIT
} WaitEventIPC;
/* ----------
--
2.18.2
From 5c64d2d3315d7e38676f349c10f94f445da2da58 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Thu, 19 Oct 2017 17:24:07 +0900
Subject: [PATCH v4 3/3] async postgres_fdw
---
contrib/postgres_fdw/connection.c | 28 +
.../postgres_fdw/expected/postgres_fdw.out | 222 ++++---
contrib/postgres_fdw/postgres_fdw.c | 601 +++++++++++++++---
contrib/postgres_fdw/postgres_fdw.h | 2 +
contrib/postgres_fdw/sql/postgres_fdw.sql | 20 +-
5 files changed, 691 insertions(+), 182 deletions(-)
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index 52d1fe3563..d9edc5e4de 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -58,6 +58,7 @@ typedef struct ConnCacheEntry
bool invalidated; /* true if reconnect is pending */
uint32 server_hashvalue; /* hash value of foreign server OID */
uint32 mapping_hashvalue; /* hash value of user mapping OID */
+ void *storage; /* connection specific storage */
} ConnCacheEntry;
/*
@@ -202,6 +203,7 @@ GetConnection(UserMapping *user, bool will_prep_stmt)
elog(DEBUG3, "new postgres_fdw connection %p for server \"%s\" (user mapping oid %u, userid %u)",
entry->conn, server->servername, user->umid, user->userid);
+ entry->storage = NULL;
}
/*
@@ -215,6 +217,32 @@ GetConnection(UserMapping *user, bool will_prep_stmt)
return entry->conn;
}
+/*
+ * Returns the connection specific storage for this user. Allocate with
+ * initsize if not exists.
+ */
+void *
+GetConnectionSpecificStorage(UserMapping *user, size_t initsize)
+{
+ bool found;
+ ConnCacheEntry *entry;
+ ConnCacheKey key;
+
+ /* Find storage using the same key with GetConnection */
+ key = user->umid;
+ entry = hash_search(ConnectionHash, &key, HASH_ENTER, &found);
+ Assert(found);
+
+ /* Create one if not yet. */
+ if (entry->storage == NULL)
+ {
+ entry->storage = MemoryContextAlloc(CacheMemoryContext, initsize);
+ memset(entry->storage, 0, initsize);
+ }
+
+ return entry->storage;
+}
+
/*
* Connect to remote server using specified server and user mapping properties.
*/
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 82fc1290ef..29aa09db8e 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -6973,7 +6973,7 @@ INSERT INTO a(aa) VALUES('aaaaa');
INSERT INTO b(aa) VALUES('bbb');
INSERT INTO b(aa) VALUES('bbbb');
INSERT INTO b(aa) VALUES('bbbbb');
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
tableoid | aa
----------+-------
a | aaa
@@ -7001,7 +7001,7 @@ SELECT tableoid::regclass, * FROM ONLY a;
(3 rows)
UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
tableoid | aa
----------+--------
a | aaa
@@ -7029,7 +7029,7 @@ SELECT tableoid::regclass, * FROM ONLY a;
(3 rows)
UPDATE b SET aa = 'new';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
tableoid | aa
----------+--------
a | aaa
@@ -7057,7 +7057,7 @@ SELECT tableoid::regclass, * FROM ONLY a;
(3 rows)
UPDATE a SET aa = 'newtoo';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
tableoid | aa
----------+--------
a | newtoo
@@ -7127,35 +7127,41 @@ insert into bar2 values(3,33,33);
insert into bar2 values(4,44,44);
insert into bar2 values(7,77,77);
explain (verbose, costs off)
-select * from bar where f1 in (select f1 from foo) for update;
- QUERY PLAN
-----------------------------------------------------------------------------------------------
+select * from bar where f1 in (select f1 from foo) order by 1 for update;
+ QUERY PLAN
+-----------------------------------------------------------------------------------------------------------------
LockRows
Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid
- -> Hash Join
+ -> Merge Join
Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid
Inner Unique: true
- Hash Cond: (bar.f1 = foo.f1)
- -> Append
- -> Seq Scan on public.bar bar_1
+ Merge Cond: (bar.f1 = foo.f1)
+ -> Merge Append
+ Sort Key: bar.f1
+ -> Sort
Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid
+ Sort Key: bar_1.f1
+ -> Seq Scan on public.bar bar_1
+ Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid
-> Foreign Scan on public.bar2 bar_2
Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid
- Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR UPDATE
- -> Hash
+ Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR UPDATE
+ -> Sort
Output: foo.ctid, foo.f1, foo.*, foo.tableoid
+ Sort Key: foo.f1
-> HashAggregate
Output: foo.ctid, foo.f1, foo.*, foo.tableoid
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo foo_1
- Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
- -> Foreign Scan on public.foo2 foo_2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2 foo_2
Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-(23 rows)
+ -> Seq Scan on public.foo foo_1
+ Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
+(29 rows)
-select * from bar where f1 in (select f1 from foo) for update;
+select * from bar where f1 in (select f1 from foo) order by 1 for update;
f1 | f2
----+----
1 | 11
@@ -7165,35 +7171,41 @@ select * from bar where f1 in (select f1 from foo) for update;
(4 rows)
explain (verbose, costs off)
-select * from bar where f1 in (select f1 from foo) for share;
- QUERY PLAN
-----------------------------------------------------------------------------------------------
+select * from bar where f1 in (select f1 from foo) order by 1 for share;
+ QUERY PLAN
+----------------------------------------------------------------------------------------------------------------
LockRows
Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid
- -> Hash Join
+ -> Merge Join
Output: bar.f1, bar.f2, bar.ctid, foo.ctid, bar.*, bar.tableoid, foo.*, foo.tableoid
Inner Unique: true
- Hash Cond: (bar.f1 = foo.f1)
- -> Append
- -> Seq Scan on public.bar bar_1
+ Merge Cond: (bar.f1 = foo.f1)
+ -> Merge Append
+ Sort Key: bar.f1
+ -> Sort
Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid
+ Sort Key: bar_1.f1
+ -> Seq Scan on public.bar bar_1
+ Output: bar_1.f1, bar_1.f2, bar_1.ctid, bar_1.*, bar_1.tableoid
-> Foreign Scan on public.bar2 bar_2
Output: bar_2.f1, bar_2.f2, bar_2.ctid, bar_2.*, bar_2.tableoid
- Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 FOR SHARE
- -> Hash
+ Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct2 ORDER BY f1 ASC NULLS LAST FOR SHARE
+ -> Sort
Output: foo.ctid, foo.f1, foo.*, foo.tableoid
+ Sort Key: foo.f1
-> HashAggregate
Output: foo.ctid, foo.f1, foo.*, foo.tableoid
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo foo_1
- Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
- -> Foreign Scan on public.foo2 foo_2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2 foo_2
Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-(23 rows)
+ -> Seq Scan on public.foo foo_1
+ Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
+(29 rows)
-select * from bar where f1 in (select f1 from foo) for share;
+select * from bar where f1 in (select f1 from foo) order by 1 for share;
f1 | f2
----+----
1 | 11
@@ -7223,11 +7235,12 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
Output: foo.ctid, foo.f1, foo.*, foo.tableoid
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo foo_1
- Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
- -> Foreign Scan on public.foo2 foo_2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2 foo_2
Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
+ -> Seq Scan on public.foo foo_1
+ Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
-> Hash Join
Output: bar_1.f1, (bar_1.f2 + 100), bar_1.f3, bar_1.ctid, foo.ctid, foo.*, foo.tableoid
Inner Unique: true
@@ -7241,12 +7254,13 @@ update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
Output: foo.ctid, foo.f1, foo.*, foo.tableoid
Group Key: foo.f1
-> Append
- -> Seq Scan on public.foo foo_1
- Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
- -> Foreign Scan on public.foo2 foo_2
+ Async subplans: 1
+ -> Async Foreign Scan on public.foo2 foo_2
Output: foo_2.ctid, foo_2.f1, foo_2.*, foo_2.tableoid
Remote SQL: SELECT f1, f2, f3, ctid FROM public.loct1
-(39 rows)
+ -> Seq Scan on public.foo foo_1
+ Output: foo_1.ctid, foo_1.f1, foo_1.*, foo_1.tableoid
+(41 rows)
update bar set f2 = f2 + 100 where f1 in (select f1 from foo);
select tableoid::regclass, * from bar order by 1,2;
@@ -7276,16 +7290,17 @@ where bar.f1 = ss.f1;
Output: bar.f1, (bar.f2 + 100), bar.ctid, (ROW(foo.f1))
Hash Cond: (foo.f1 = bar.f1)
-> Append
+ Async subplans: 2
+ -> Async Foreign Scan on public.foo2 foo_1
+ Output: ROW(foo_1.f1), foo_1.f1
+ Remote SQL: SELECT f1 FROM public.loct1
+ -> Async Foreign Scan on public.foo2 foo_3
+ Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3)
+ Remote SQL: SELECT f1 FROM public.loct1
-> Seq Scan on public.foo
Output: ROW(foo.f1), foo.f1
- -> Foreign Scan on public.foo2 foo_1
- Output: ROW(foo_1.f1), foo_1.f1
- Remote SQL: SELECT f1 FROM public.loct1
-> Seq Scan on public.foo foo_2
Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3)
- -> Foreign Scan on public.foo2 foo_3
- Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3)
- Remote SQL: SELECT f1 FROM public.loct1
-> Hash
Output: bar.f1, bar.f2, bar.ctid
-> Seq Scan on public.bar
@@ -7303,17 +7318,18 @@ where bar.f1 = ss.f1;
Output: (ROW(foo.f1)), foo.f1
Sort Key: foo.f1
-> Append
+ Async subplans: 2
+ -> Async Foreign Scan on public.foo2 foo_1
+ Output: ROW(foo_1.f1), foo_1.f1
+ Remote SQL: SELECT f1 FROM public.loct1
+ -> Async Foreign Scan on public.foo2 foo_3
+ Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3)
+ Remote SQL: SELECT f1 FROM public.loct1
-> Seq Scan on public.foo
Output: ROW(foo.f1), foo.f1
- -> Foreign Scan on public.foo2 foo_1
- Output: ROW(foo_1.f1), foo_1.f1
- Remote SQL: SELECT f1 FROM public.loct1
-> Seq Scan on public.foo foo_2
Output: ROW((foo_2.f1 + 3)), (foo_2.f1 + 3)
- -> Foreign Scan on public.foo2 foo_3
- Output: ROW((foo_3.f1 + 3)), (foo_3.f1 + 3)
- Remote SQL: SELECT f1 FROM public.loct1
-(45 rows)
+(47 rows)
update bar set f2 = f2 + 100
from
@@ -7463,27 +7479,33 @@ delete from foo where f1 < 5 returning *;
(5 rows)
explain (verbose, costs off)
-update bar set f2 = f2 + 100 returning *;
- QUERY PLAN
-------------------------------------------------------------------------------
- Update on public.bar
- Output: bar.f1, bar.f2
- Update on public.bar
- Foreign Update on public.bar2 bar_1
- -> Seq Scan on public.bar
- Output: bar.f1, (bar.f2 + 100), bar.ctid
- -> Foreign Update on public.bar2 bar_1
- Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2
-(8 rows)
+with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1;
+ QUERY PLAN
+--------------------------------------------------------------------------------------
+ Sort
+ Output: u.f1, u.f2
+ Sort Key: u.f1
+ CTE u
+ -> Update on public.bar
+ Output: bar.f1, bar.f2
+ Update on public.bar
+ Foreign Update on public.bar2 bar_1
+ -> Seq Scan on public.bar
+ Output: bar.f1, (bar.f2 + 100), bar.ctid
+ -> Foreign Update on public.bar2 bar_1
+ Remote SQL: UPDATE public.loct2 SET f2 = (f2 + 100) RETURNING f1, f2
+ -> CTE Scan on u
+ Output: u.f1, u.f2
+(14 rows)
-update bar set f2 = f2 + 100 returning *;
+with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1;
f1 | f2
----+-----
1 | 311
2 | 322
- 6 | 266
3 | 333
4 | 344
+ 6 | 266
7 | 277
(6 rows)
@@ -8558,11 +8580,12 @@ SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER J
Sort
Sort Key: t1.a, t3.c
-> Append
- -> Foreign Scan
+ Async subplans: 2
+ -> Async Foreign Scan
Relations: ((ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)) INNER JOIN (ftprt1_p1 t3_1)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: ((ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)) INNER JOIN (ftprt1_p2 t3_2)
-(7 rows)
+(8 rows)
SELECT t1.a,t2.b,t3.c FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) INNER JOIN fprt1 t3 ON (t2.b = t3.a) WHERE
t1.a% 25 =0 ORDER BY 1,2,3;
a | b | c
@@ -8597,20 +8620,22 @@ SELECT t1.a,t2.b,t2.c FROM fprt1 t1 LEFT JOIN (SELECT * FROM fprt2 WHERE a < 10)
-- with whole-row reference; partitionwise join does not apply
EXPLAIN (COSTS OFF)
SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2
t2WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2;
- QUERY PLAN
---------------------------------------------------------
+ QUERY PLAN
+--------------------------------------------------------------
Sort
Sort Key: ((t1.*)::fprt1), ((t2.*)::fprt2)
-> Hash Full Join
Hash Cond: (t1.a = t2.b)
-> Append
- -> Foreign Scan on ftprt1_p1 t1_1
- -> Foreign Scan on ftprt1_p2 t1_2
+ Async subplans: 2
+ -> Async Foreign Scan on ftprt1_p1 t1_1
+ -> Async Foreign Scan on ftprt1_p2 t1_2
-> Hash
-> Append
- -> Foreign Scan on ftprt2_p1 t2_1
- -> Foreign Scan on ftprt2_p2 t2_2
-(11 rows)
+ Async subplans: 2
+ -> Async Foreign Scan on ftprt2_p1 t2_1
+ -> Async Foreign Scan on ftprt2_p2 t2_2
+(13 rows)
SELECT t1.wr, t2.wr FROM (SELECT t1 wr, a FROM fprt1 t1 WHERE t1.a % 25 = 0) t1 FULL JOIN (SELECT t2 wr, b FROM fprt2
t2WHERE t2.b % 25 = 0) t2 ON (t1.a = t2.b) ORDER BY 1,2;
wr | wr
@@ -8639,11 +8664,12 @@ SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t
Sort
Sort Key: t1.a, t1.b
-> Append
- -> Foreign Scan
+ Async subplans: 2
+ -> Async Foreign Scan
Relations: (ftprt1_p1 t1_1) INNER JOIN (ftprt2_p1 t2_1)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: (ftprt1_p2 t1_2) INNER JOIN (ftprt2_p2 t2_2)
-(7 rows)
+(8 rows)
SELECT t1.a,t1.b FROM fprt1 t1, LATERAL (SELECT t2.a, t2.b FROM fprt2 t2 WHERE t1.a = t2.b AND t1.b = t2.a) q WHERE
t1.a%25= 0 ORDER BY 1,2;
a | b
@@ -8696,21 +8722,23 @@ SELECT t1.a, t1.phv, t2.b, t2.phv FROM (SELECT 't1_phv' phv, * FROM fprt1 WHERE
-- test FOR UPDATE; partitionwise join does not apply
EXPLAIN (COSTS OFF)
SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF
t1;
- QUERY PLAN
---------------------------------------------------------------
+ QUERY PLAN
+--------------------------------------------------------------------
LockRows
-> Sort
Sort Key: t1.a
-> Hash Join
Hash Cond: (t2.b = t1.a)
-> Append
- -> Foreign Scan on ftprt2_p1 t2_1
- -> Foreign Scan on ftprt2_p2 t2_2
+ Async subplans: 2
+ -> Async Foreign Scan on ftprt2_p1 t2_1
+ -> Async Foreign Scan on ftprt2_p2 t2_2
-> Hash
-> Append
- -> Foreign Scan on ftprt1_p1 t1_1
- -> Foreign Scan on ftprt1_p2 t1_2
-(12 rows)
+ Async subplans: 2
+ -> Async Foreign Scan on ftprt1_p1 t1_1
+ -> Async Foreign Scan on ftprt1_p2 t1_2
+(14 rows)
SELECT t1.a, t2.b FROM fprt1 t1 INNER JOIN fprt2 t2 ON (t1.a = t2.b) WHERE t1.a % 25 = 0 ORDER BY 1,2 FOR UPDATE OF
t1;
a | b
@@ -8745,18 +8773,19 @@ ANALYZE fpagg_tab_p3;
SET enable_partitionwise_aggregate TO false;
EXPLAIN (COSTS OFF)
SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1;
- QUERY PLAN
------------------------------------------------------------
+ QUERY PLAN
+-----------------------------------------------------------------
Sort
Sort Key: pagg_tab.a
-> HashAggregate
Group Key: pagg_tab.a
Filter: (avg(pagg_tab.b) < '22'::numeric)
-> Append
- -> Foreign Scan on fpagg_tab_p1 pagg_tab_1
- -> Foreign Scan on fpagg_tab_p2 pagg_tab_2
- -> Foreign Scan on fpagg_tab_p3 pagg_tab_3
-(9 rows)
+ Async subplans: 3
+ -> Async Foreign Scan on fpagg_tab_p1 pagg_tab_1
+ -> Async Foreign Scan on fpagg_tab_p2 pagg_tab_2
+ -> Async Foreign Scan on fpagg_tab_p3 pagg_tab_3
+(10 rows)
-- Plan with partitionwise aggregates is enabled
SET enable_partitionwise_aggregate TO true;
@@ -8767,13 +8796,14 @@ SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 O
Sort
Sort Key: pagg_tab.a
-> Append
- -> Foreign Scan
+ Async subplans: 3
+ -> Async Foreign Scan
Relations: Aggregate on (fpagg_tab_p1 pagg_tab)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: Aggregate on (fpagg_tab_p2 pagg_tab_1)
- -> Foreign Scan
+ -> Async Foreign Scan
Relations: Aggregate on (fpagg_tab_p3 pagg_tab_2)
-(9 rows)
+(10 rows)
SELECT a, sum(b), min(b), count(*) FROM pagg_tab GROUP BY a HAVING avg(b) < 22 ORDER BY 1;
a | sum | min | count
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 9fc53cad68..4bfc2d39ea 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -21,6 +21,8 @@
#include "commands/defrem.h"
#include "commands/explain.h"
#include "commands/vacuum.h"
+#include "executor/execAsync.h"
+#include "executor/nodeForeignscan.h"
#include "foreign/fdwapi.h"
#include "funcapi.h"
#include "miscadmin.h"
@@ -35,6 +37,7 @@
#include "optimizer/restrictinfo.h"
#include "optimizer/tlist.h"
#include "parser/parsetree.h"
+#include "pgstat.h"
#include "postgres_fdw.h"
#include "utils/builtins.h"
#include "utils/float.h"
@@ -56,6 +59,9 @@ PG_MODULE_MAGIC;
/* If no remote estimates, assume a sort costs 20% extra */
#define DEFAULT_FDW_SORT_MULTIPLIER 1.2
+/* Retrieve PgFdwScanState struct from ForeignScanState */
+#define GetPgFdwScanState(n) ((PgFdwScanState *)(n)->fdw_state)
+
/*
* Indexes of FDW-private information stored in fdw_private lists.
*
@@ -122,11 +128,29 @@ enum FdwDirectModifyPrivateIndex
FdwDirectModifyPrivateSetProcessed
};
+/*
+ * Connection common state - shared among all PgFdwState instances using the
+ * same connection.
+ */
+typedef struct PgFdwConnCommonState
+{
+ ForeignScanState *leader; /* leader node of this connection */
+ bool busy; /* true if this connection is busy */
+} PgFdwConnCommonState;
+
+/* Execution state base type */
+typedef struct PgFdwState
+{
+ PGconn *conn; /* connection for the scan */
+ PgFdwConnCommonState *commonstate; /* connection common state */
+} PgFdwState;
+
/*
* Execution state of a foreign scan using postgres_fdw.
*/
typedef struct PgFdwScanState
{
+ PgFdwState s; /* common structure */
Relation rel; /* relcache entry for the foreign table. NULL
* for a foreign join scan. */
TupleDesc tupdesc; /* tuple descriptor of scan */
@@ -137,7 +161,6 @@ typedef struct PgFdwScanState
List *retrieved_attrs; /* list of retrieved attribute numbers */
/* for remote query execution */
- PGconn *conn; /* connection for the scan */
unsigned int cursor_number; /* quasi-unique ID for my cursor */
bool cursor_exists; /* have we created the cursor? */
int numParams; /* number of parameters passed to query */
@@ -153,6 +176,12 @@ typedef struct PgFdwScanState
/* batch-level state, for optimizing rewinds and avoiding useless fetch */
int fetch_ct_2; /* Min(# of fetches done, 2) */
bool eof_reached; /* true if last fetch reached EOF */
+ bool async; /* true if run asynchronously */
+ bool queued; /* true if this node is in waiter queue */
+ ForeignScanState *waiter; /* Next node to run a query among nodes
+ * sharing the same connection */
+ ForeignScanState *last_waiter; /* last element in waiter queue.
+ * valid only on the leader node */
/* working memory contexts */
MemoryContext batch_cxt; /* context holding current batch of tuples */
@@ -166,11 +195,11 @@ typedef struct PgFdwScanState
*/
typedef struct PgFdwModifyState
{
+ PgFdwState s; /* common structure */
Relation rel; /* relcache entry for the foreign table */
AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
/* for remote query execution */
- PGconn *conn; /* connection for the scan */
char *p_name; /* name of prepared statement, if created */
/* extracted fdw_private data */
@@ -197,6 +226,7 @@ typedef struct PgFdwModifyState
*/
typedef struct PgFdwDirectModifyState
{
+ PgFdwState s; /* common structure */
Relation rel; /* relcache entry for the foreign table */
AttInMetadata *attinmeta; /* attribute datatype conversion metadata */
@@ -326,6 +356,7 @@ static void postgresBeginForeignScan(ForeignScanState *node, int eflags);
static TupleTableSlot *postgresIterateForeignScan(ForeignScanState *node);
static void postgresReScanForeignScan(ForeignScanState *node);
static void postgresEndForeignScan(ForeignScanState *node);
+static void postgresShutdownForeignScan(ForeignScanState *node);
static void postgresAddForeignUpdateTargets(Query *parsetree,
RangeTblEntry *target_rte,
Relation target_relation);
@@ -391,6 +422,10 @@ static void postgresGetForeignUpperPaths(PlannerInfo *root,
RelOptInfo *input_rel,
RelOptInfo *output_rel,
void *extra);
+static bool postgresIsForeignPathAsyncCapable(ForeignPath *path);
+static bool postgresForeignAsyncConfigureWait(ForeignScanState *node,
+ WaitEventSet *wes,
+ void *caller_data, bool reinit);
/*
* Helper functions
@@ -419,7 +454,9 @@ static bool ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel,
EquivalenceClass *ec, EquivalenceMember *em,
void *arg);
static void create_cursor(ForeignScanState *node);
-static void fetch_more_data(ForeignScanState *node);
+static void request_more_data(ForeignScanState *node);
+static void fetch_received_data(ForeignScanState *node);
+static void vacate_connection(PgFdwState *fdwconn, bool clear_queue);
static void close_cursor(PGconn *conn, unsigned int cursor_number);
static PgFdwModifyState *create_foreign_modify(EState *estate,
RangeTblEntry *rte,
@@ -522,6 +559,7 @@ postgres_fdw_handler(PG_FUNCTION_ARGS)
routine->IterateForeignScan = postgresIterateForeignScan;
routine->ReScanForeignScan = postgresReScanForeignScan;
routine->EndForeignScan = postgresEndForeignScan;
+ routine->ShutdownForeignScan = postgresShutdownForeignScan;
/* Functions for updating foreign tables */
routine->AddForeignUpdateTargets = postgresAddForeignUpdateTargets;
@@ -558,6 +596,10 @@ postgres_fdw_handler(PG_FUNCTION_ARGS)
/* Support functions for upper relation push-down */
routine->GetForeignUpperPaths = postgresGetForeignUpperPaths;
+ /* Support functions for async execution */
+ routine->IsForeignPathAsyncCapable = postgresIsForeignPathAsyncCapable;
+ routine->ForeignAsyncConfigureWait = postgresForeignAsyncConfigureWait;
+
PG_RETURN_POINTER(routine);
}
@@ -1434,12 +1476,22 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags)
* Get connection to the foreign server. Connection manager will
* establish new connection if necessary.
*/
- fsstate->conn = GetConnection(user, false);
+ fsstate->s.conn = GetConnection(user, false);
+ fsstate->s.commonstate = (PgFdwConnCommonState *)
+ GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState));
+ fsstate->s.commonstate->leader = NULL;
+ fsstate->s.commonstate->busy = false;
+ fsstate->waiter = NULL;
+ fsstate->last_waiter = node;
/* Assign a unique ID for my cursor */
- fsstate->cursor_number = GetCursorNumber(fsstate->conn);
+ fsstate->cursor_number = GetCursorNumber(fsstate->s.conn);
fsstate->cursor_exists = false;
+ /* Initialize async execution status */
+ fsstate->async = false;
+ fsstate->queued = false;
+
/* Get private info created by planner functions. */
fsstate->query = strVal(list_nth(fsplan->fdw_private,
FdwScanPrivateSelectSql));
@@ -1487,40 +1539,241 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags)
&fsstate->param_values);
}
+/*
+ * Async queue manipulation functions
+ */
+
+/*
+ * add_async_waiter:
+ *
+ * Enqueue node if it isn't in the queue. Immediately send request it if the
+ * underlying connection is not busy.
+ */
+static inline void
+add_async_waiter(ForeignScanState *node)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+ ForeignScanState *leader = fsstate->s.commonstate->leader;
+
+ /*
+ * Do nothing if the node is already in the queue or already eof'ed.
+ * Note: leader node is not marked as queued.
+ */
+ if (leader == node || fsstate->queued || fsstate->eof_reached)
+ return;
+
+ if (leader == NULL)
+ {
+ /* no leader means not busy, send request immediately */
+ request_more_data(node);
+ }
+ else
+ {
+ /* the connection is busy, queue the node */
+ PgFdwScanState *leader_state = GetPgFdwScanState(leader);
+ PgFdwScanState *last_waiter_state
+ = GetPgFdwScanState(leader_state->last_waiter);
+
+ last_waiter_state->waiter = node;
+ leader_state->last_waiter = node;
+ fsstate->queued = true;
+ }
+}
+
+/*
+ * move_to_next_waiter:
+ *
+ * Make the first waiter be the next leader
+ * Returns the new leader or NULL if there's no waiter.
+ */
+static inline ForeignScanState *
+move_to_next_waiter(ForeignScanState *node)
+{
+ PgFdwScanState *leader_state = GetPgFdwScanState(node);
+ ForeignScanState *next_leader = leader_state->waiter;
+
+ Assert(leader_state->s.commonstate->leader = node);
+
+ if (next_leader)
+ {
+ /* the first waiter becomes the next leader */
+ PgFdwScanState *next_leader_state = GetPgFdwScanState(next_leader);
+ next_leader_state->last_waiter = leader_state->last_waiter;
+ next_leader_state->queued = false;
+ }
+
+ leader_state->waiter = NULL;
+ leader_state->s.commonstate->leader = next_leader;
+
+ return next_leader;
+}
+
+/*
+ * Remove the node from waiter queue.
+ *
+ * Remaining results are cleared if the node is a busy leader.
+ * This intended to be used during node shutdown.
+ */
+static inline void
+remove_async_node(ForeignScanState *node)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+ ForeignScanState *leader = fsstate->s.commonstate->leader;
+ PgFdwScanState *leader_state;
+ ForeignScanState *prev;
+ PgFdwScanState *prev_state;
+ ForeignScanState *cur;
+
+ /* no need to remove me */
+ if (!leader || !fsstate->queued)
+ return;
+
+ leader_state = GetPgFdwScanState(leader);
+
+ if (leader == node)
+ {
+ if (leader_state->s.commonstate->busy)
+ {
+ /*
+ * this node is waiting for result, absorb the result first so
+ * that the following commands can be sent on the connection.
+ */
+ PgFdwScanState *leader_state = GetPgFdwScanState(leader);
+ PGconn *conn = leader_state->s.conn;
+
+ while(PQisBusy(conn))
+ PQclear(PQgetResult(conn));
+
+ leader_state->s.commonstate->busy = false;
+ }
+
+ move_to_next_waiter(node);
+
+ return;
+ }
+
+ /*
+ * Just remove the node from the queue
+ *
+ * Nodes don't have a link to the previous node but anyway this function is
+ * called on the shutdown path, so we don't bother seeking for faster way
+ * to do this.
+ */
+ prev = leader;
+ prev_state = leader_state;
+ cur = GetPgFdwScanState(prev)->waiter;
+ while (cur)
+ {
+ PgFdwScanState *curstate = GetPgFdwScanState(cur);
+
+ if (cur == node)
+ {
+ prev_state->waiter = curstate->waiter;
+
+ /* relink to the previous node if the last node was removed */
+ if (leader_state->last_waiter == cur)
+ leader_state->last_waiter = prev;
+
+ fsstate->queued = false;
+
+ return;
+ }
+ prev = cur;
+ prev_state = curstate;
+ cur = curstate->waiter;
+ }
+}
+
/*
* postgresIterateForeignScan
- * Retrieve next row from the result set, or clear tuple slot to indicate
- * EOF.
+ * Retrieve next row from the result set.
+ *
+ * For synchronous nodes, returns clear tuple slot means EOF.
+ *
+ * For asynchronous nodes, if clear tuple slot is returned, the caller
+ * needs to check async state to tell if all tuples received
+ * (AS_AVAILABLE) or waiting for the next data to come (AS_WAITING).
*/
static TupleTableSlot *
postgresIterateForeignScan(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
TupleTableSlot *slot = node->ss.ss_ScanTupleSlot;
- /*
- * If this is the first call after Begin or ReScan, we need to create the
- * cursor on the remote side.
- */
- if (!fsstate->cursor_exists)
- create_cursor(node);
-
- /*
- * Get some more tuples, if we've run out.
- */
+ if (fsstate->next_tuple >= fsstate->num_tuples && !fsstate->eof_reached)
+ {
+ /* we've run out, get some more tuples */
+ if (!node->fs_async)
+ {
+ /*
+ * finish the running query before sending the next command for
+ * this node
+ */
+ if (!fsstate->s.commonstate->busy)
+ vacate_connection((PgFdwState *)fsstate, false);
+
+ request_more_data(node);
+
+ /* Fetch the result immediately. */
+ fetch_received_data(node);
+ }
+ else if (!fsstate->s.commonstate->busy)
+ {
+ /* If the connection is not busy, just send the request. */
+ request_more_data(node);
+ }
+ else
+ {
+ /* The connection is busy, queue the request */
+ bool available = true;
+ ForeignScanState *leader = fsstate->s.commonstate->leader;
+ PgFdwScanState *leader_state = GetPgFdwScanState(leader);
+
+ /* queue the requested node */
+ add_async_waiter(node);
+
+ /*
+ * The request for the next node cannot be sent before the leader
+ * responds. Finish the current leader if possible.
+ */
+ if (PQisBusy(leader_state->s.conn))
+ {
+ int rc = WaitLatchOrSocket(NULL,
+ WL_SOCKET_READABLE | WL_TIMEOUT |
+ WL_EXIT_ON_PM_DEATH,
+ PQsocket(leader_state->s.conn), 0,
+ WAIT_EVENT_ASYNC_WAIT);
+ if (!(rc & WL_SOCKET_READABLE))
+ available = false;
+ }
+
+ /* fetch the leader's data and enqueue it for the next request */
+ if (available)
+ {
+ fetch_received_data(leader);
+ add_async_waiter(leader);
+ }
+ }
+ }
+
if (fsstate->next_tuple >= fsstate->num_tuples)
{
- /* No point in another fetch if we already detected EOF, though. */
- if (!fsstate->eof_reached)
- fetch_more_data(node);
- /* If we didn't get any tuples, must be end of data. */
- if (fsstate->next_tuple >= fsstate->num_tuples)
- return ExecClearTuple(slot);
+ /*
+ * We haven't received a result for the given node this time, return
+ * with no tuple to give way to another node.
+ */
+ if (fsstate->eof_reached)
+ node->ss.ps.asyncstate = AS_AVAILABLE;
+ else
+ node->ss.ps.asyncstate = AS_WAITING;
+
+ return ExecClearTuple(slot);
}
/*
* Return the next tuple.
*/
+ node->ss.ps.asyncstate = AS_AVAILABLE;
ExecStoreHeapTuple(fsstate->tuples[fsstate->next_tuple++],
slot,
false);
@@ -1535,7 +1788,7 @@ postgresIterateForeignScan(ForeignScanState *node)
static void
postgresReScanForeignScan(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
char sql[64];
PGresult *res;
@@ -1543,6 +1796,8 @@ postgresReScanForeignScan(ForeignScanState *node)
if (!fsstate->cursor_exists)
return;
+ vacate_connection((PgFdwState *)fsstate, true);
+
/*
* If any internal parameters affecting this node have changed, we'd
* better destroy and recreate the cursor. Otherwise, rewinding it should
@@ -1571,9 +1826,9 @@ postgresReScanForeignScan(ForeignScanState *node)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_exec_query(fsstate->conn, sql);
+ res = pgfdw_exec_query(fsstate->s.conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, fsstate->conn, true, sql);
+ pgfdw_report_error(ERROR, res, fsstate->s.conn, true, sql);
PQclear(res);
/* Now force a fresh FETCH. */
@@ -1591,7 +1846,7 @@ postgresReScanForeignScan(ForeignScanState *node)
static void
postgresEndForeignScan(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
/* if fsstate is NULL, we are in EXPLAIN; nothing to do */
if (fsstate == NULL)
@@ -1599,15 +1854,31 @@ postgresEndForeignScan(ForeignScanState *node)
/* Close the cursor if open, to prevent accumulation of cursors */
if (fsstate->cursor_exists)
- close_cursor(fsstate->conn, fsstate->cursor_number);
+ close_cursor(fsstate->s.conn, fsstate->cursor_number);
/* Release remote connection */
- ReleaseConnection(fsstate->conn);
- fsstate->conn = NULL;
+ ReleaseConnection(fsstate->s.conn);
+ fsstate->s.conn = NULL;
/* MemoryContexts will be deleted automatically. */
}
+/*
+ * postgresShutdownForeignScan
+ * Remove asynchrony stuff and cleanup garbage on the connection.
+ */
+static void
+postgresShutdownForeignScan(ForeignScanState *node)
+{
+ ForeignScan *plan = (ForeignScan *) node->ss.ps.plan;
+
+ if (plan->operation != CMD_SELECT)
+ return;
+
+ /* remove the node from waiting queue */
+ remove_async_node(node);
+}
+
/*
* postgresAddForeignUpdateTargets
* Add resjunk column(s) needed for update/delete on a foreign table
@@ -2372,7 +2643,9 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags)
* Get connection to the foreign server. Connection manager will
* establish new connection if necessary.
*/
- dmstate->conn = GetConnection(user, false);
+ dmstate->s.conn = GetConnection(user, false);
+ dmstate->s.commonstate = (PgFdwConnCommonState *)
+ GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState));
/* Update the foreign-join-related fields. */
if (fsplan->scan.scanrelid == 0)
@@ -2457,7 +2730,11 @@ postgresIterateDirectModify(ForeignScanState *node)
* If this is the first call after Begin, execute the statement.
*/
if (dmstate->num_tuples == -1)
+ {
+ /* finish running query to send my command */
+ vacate_connection((PgFdwState *)dmstate, true);
execute_dml_stmt(node);
+ }
/*
* If the local query doesn't specify RETURNING, just clear tuple slot.
@@ -2504,8 +2781,8 @@ postgresEndDirectModify(ForeignScanState *node)
PQclear(dmstate->result);
/* Release remote connection */
- ReleaseConnection(dmstate->conn);
- dmstate->conn = NULL;
+ ReleaseConnection(dmstate->s.conn);
+ dmstate->s.conn = NULL;
/* MemoryContext will be deleted automatically. */
}
@@ -2703,6 +2980,7 @@ estimate_path_cost_size(PlannerInfo *root,
List *local_param_join_conds;
StringInfoData sql;
PGconn *conn;
+ PgFdwConnCommonState *commonstate;
Selectivity local_sel;
QualCost local_cost;
List *fdw_scan_tlist = NIL;
@@ -2747,6 +3025,18 @@ estimate_path_cost_size(PlannerInfo *root,
/* Get the remote estimate */
conn = GetConnection(fpinfo->user, false);
+ commonstate = GetConnectionSpecificStorage(fpinfo->user,
+ sizeof(PgFdwConnCommonState));
+ if (commonstate)
+ {
+ PgFdwState tmpstate;
+ tmpstate.conn = conn;
+ tmpstate.commonstate = commonstate;
+
+ /* finish running query to send my command */
+ vacate_connection(&tmpstate, true);
+ }
+
get_remote_estimate(sql.data, conn, &rows, &width,
&startup_cost, &total_cost);
ReleaseConnection(conn);
@@ -3317,11 +3607,11 @@ ec_member_matches_foreign(PlannerInfo *root, RelOptInfo *rel,
static void
create_cursor(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
ExprContext *econtext = node->ss.ps.ps_ExprContext;
int numParams = fsstate->numParams;
const char **values = fsstate->param_values;
- PGconn *conn = fsstate->conn;
+ PGconn *conn = fsstate->s.conn;
StringInfoData buf;
PGresult *res;
@@ -3384,50 +3674,119 @@ create_cursor(ForeignScanState *node)
}
/*
- * Fetch some more rows from the node's cursor.
+ * Sends the next request of the node. If the given node is different from the
+ * current connection leader, pushes it back to waiter queue and let the given
+ * node be the leader.
*/
static void
-fetch_more_data(ForeignScanState *node)
+request_more_data(ForeignScanState *node)
{
- PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+ ForeignScanState *leader = fsstate->s.commonstate->leader;
+ PGconn *conn = fsstate->s.conn;
+ char sql[64];
+
+ /* must be non-busy */
+ Assert(!fsstate->s.commonstate->busy);
+ /* must be not-eof'ed */
+ Assert(!fsstate->eof_reached);
+
+ /*
+ * If this is the first call after Begin or ReScan, we need to create the
+ * cursor on the remote side.
+ */
+ if (!fsstate->cursor_exists)
+ create_cursor(node);
+
+ snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
+ fsstate->fetch_size, fsstate->cursor_number);
+
+ if (!PQsendQuery(conn, sql))
+ pgfdw_report_error(ERROR, NULL, conn, false, sql);
+
+ fsstate->s.commonstate->busy = true;
+
+ /* The node is the current leader, just return. */
+ if (leader == node)
+ return;
+
+ /* Let the node be the leader */
+ if (leader != NULL)
+ {
+ remove_async_node(node);
+ fsstate->last_waiter = GetPgFdwScanState(leader)->last_waiter;
+ fsstate->waiter = leader;
+ }
+ else
+ {
+ fsstate->last_waiter = node;
+ fsstate->waiter = NULL;
+ }
+
+ fsstate->s.commonstate->leader = node;
+}
+
+/*
+ * Fetches received data and automatically send requests of the next waiter.
+ */
+static void
+fetch_received_data(ForeignScanState *node)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
PGresult *volatile res = NULL;
MemoryContext oldcontext;
+ ForeignScanState *waiter;
+
+ /* I should be the current connection leader */
+ Assert(fsstate->s.commonstate->leader == node);
/*
* We'll store the tuples in the batch_cxt. First, flush the previous
- * batch.
+ * batch if no tuple is remaining
*/
- fsstate->tuples = NULL;
- MemoryContextReset(fsstate->batch_cxt);
+ if (fsstate->next_tuple >= fsstate->num_tuples)
+ {
+ fsstate->tuples = NULL;
+ fsstate->num_tuples = 0;
+ MemoryContextReset(fsstate->batch_cxt);
+ }
+ else if (fsstate->next_tuple > 0)
+ {
+ /* There's some remains. Move them to the beginning of the store */
+ int n = 0;
+
+ while(fsstate->next_tuple < fsstate->num_tuples)
+ fsstate->tuples[n++] = fsstate->tuples[fsstate->next_tuple++];
+ fsstate->num_tuples = n;
+ }
+
oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt);
/* PGresult must be released before leaving this function. */
PG_TRY();
{
- PGconn *conn = fsstate->conn;
- char sql[64];
- int numrows;
+ PGconn *conn = fsstate->s.conn;
+ int addrows;
+ size_t newsize;
int i;
- snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
- fsstate->fetch_size, fsstate->cursor_number);
-
- res = pgfdw_exec_query(conn, sql);
- /* On error, report the original query, not the FETCH. */
+ res = pgfdw_get_result(conn, fsstate->query);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
pgfdw_report_error(ERROR, res, conn, false, fsstate->query);
/* Convert the data into HeapTuples */
- numrows = PQntuples(res);
- fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple));
- fsstate->num_tuples = numrows;
- fsstate->next_tuple = 0;
+ addrows = PQntuples(res);
+ newsize = (fsstate->num_tuples + addrows) * sizeof(HeapTuple);
+ if (fsstate->tuples)
+ fsstate->tuples = (HeapTuple *) repalloc(fsstate->tuples, newsize);
+ else
+ fsstate->tuples = (HeapTuple *) palloc(newsize);
- for (i = 0; i < numrows; i++)
+ for (i = 0; i < addrows; i++)
{
Assert(IsA(node->ss.ps.plan, ForeignScan));
- fsstate->tuples[i] =
+ fsstate->tuples[fsstate->num_tuples + i] =
make_tuple_from_result_row(res, i,
fsstate->rel,
fsstate->attinmeta,
@@ -3437,22 +3796,73 @@ fetch_more_data(ForeignScanState *node)
}
/* Update fetch_ct_2 */
- if (fsstate->fetch_ct_2 < 2)
+ if (fsstate->fetch_ct_2 < 2 && fsstate->next_tuple == 0)
fsstate->fetch_ct_2++;
+ fsstate->next_tuple = 0;
+ fsstate->num_tuples += addrows;
+
/* Must be EOF if we didn't get as many tuples as we asked for. */
- fsstate->eof_reached = (numrows < fsstate->fetch_size);
+ fsstate->eof_reached = (addrows < fsstate->fetch_size);
}
PG_FINALLY();
{
+ fsstate->s.commonstate->busy = false;
+
if (res)
PQclear(res);
}
PG_END_TRY();
+ /* let the first waiter be the next leader of this connection */
+ waiter = move_to_next_waiter(node);
+
+ /* send the next request if any */
+ if (waiter)
+ request_more_data(waiter);
+
MemoryContextSwitchTo(oldcontext);
}
+/*
+ * Vacate the underlying connection so that this node can send the next query.
+ */
+static void
+vacate_connection(PgFdwState *fdwstate, bool clear_queue)
+{
+ PgFdwConnCommonState *commonstate = fdwstate->commonstate;
+ ForeignScanState *leader;
+
+ Assert(commonstate != NULL);
+
+ /* just return if the connection is already available */
+ if (commonstate->leader == NULL || !commonstate->busy)
+ return;
+
+ /*
+ * let the current connection leader read all of the result for the running
+ * query
+ */
+ leader = commonstate->leader;
+ fetch_received_data(leader);
+
+ /* let the first waiter be the next leader of this connection */
+ move_to_next_waiter(leader);
+
+ if (!clear_queue)
+ return;
+
+ /* Clear the waiting list */
+ while (leader)
+ {
+ PgFdwScanState *fsstate = GetPgFdwScanState(leader);
+
+ fsstate->last_waiter = NULL;
+ leader = fsstate->waiter;
+ fsstate->waiter = NULL;
+ }
+}
+
/*
* Force assorted GUC parameters to settings that ensure that we'll output
* data values in a form that is unambiguous to the remote server.
@@ -3566,7 +3976,9 @@ create_foreign_modify(EState *estate,
user = GetUserMapping(userid, table->serverid);
/* Open connection; report that we'll create a prepared statement. */
- fmstate->conn = GetConnection(user, true);
+ fmstate->s.conn = GetConnection(user, true);
+ fmstate->s.commonstate = (PgFdwConnCommonState *)
+ GetConnectionSpecificStorage(user, sizeof(PgFdwConnCommonState));
fmstate->p_name = NULL; /* prepared statement not made yet */
/* Set up remote query information. */
@@ -3653,6 +4065,9 @@ execute_foreign_modify(EState *estate,
operation == CMD_UPDATE ||
operation == CMD_DELETE);
+ /* finish running query to send my command */
+ vacate_connection((PgFdwState *)fmstate, true);
+
/* Set up the prepared statement on the remote server, if we didn't yet */
if (!fmstate->p_name)
prepare_foreign_modify(fmstate);
@@ -3680,14 +4095,14 @@ execute_foreign_modify(EState *estate,
/*
* Execute the prepared statement.
*/
- if (!PQsendQueryPrepared(fmstate->conn,
+ if (!PQsendQueryPrepared(fmstate->s.conn,
fmstate->p_name,
fmstate->p_nums,
p_values,
NULL,
NULL,
0))
- pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+ pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query);
/*
* Get the result, and check for success.
@@ -3695,10 +4110,10 @@ execute_foreign_modify(EState *estate,
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_get_result(fmstate->conn, fmstate->query);
+ res = pgfdw_get_result(fmstate->s.conn, fmstate->query);
if (PQresultStatus(res) !=
(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query);
/* Check number of rows affected, and fetch RETURNING tuple if any */
if (fmstate->has_returning)
@@ -3734,7 +4149,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
/* Construct name we'll use for the prepared statement. */
snprintf(prep_name, sizeof(prep_name), "pgsql_fdw_prep_%u",
- GetPrepStmtNumber(fmstate->conn));
+ GetPrepStmtNumber(fmstate->s.conn));
p_name = pstrdup(prep_name);
/*
@@ -3744,12 +4159,12 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
* the prepared statements we use in this module are simple enough that
* the remote server will make the right choices.
*/
- if (!PQsendPrepare(fmstate->conn,
+ if (!PQsendPrepare(fmstate->s.conn,
p_name,
fmstate->query,
0,
NULL))
- pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+ pgfdw_report_error(ERROR, NULL, fmstate->s.conn, false, fmstate->query);
/*
* Get the result, and check for success.
@@ -3757,9 +4172,9 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_get_result(fmstate->conn, fmstate->query);
+ res = pgfdw_get_result(fmstate->s.conn, fmstate->query);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, fmstate->query);
PQclear(res);
/* This action shows that the prepare has been done. */
@@ -3888,16 +4303,16 @@ finish_foreign_modify(PgFdwModifyState *fmstate)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- res = pgfdw_exec_query(fmstate->conn, sql);
+ res = pgfdw_exec_query(fmstate->s.conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, fmstate->conn, true, sql);
+ pgfdw_report_error(ERROR, res, fmstate->s.conn, true, sql);
PQclear(res);
fmstate->p_name = NULL;
}
/* Release remote connection */
- ReleaseConnection(fmstate->conn);
- fmstate->conn = NULL;
+ ReleaseConnection(fmstate->s.conn);
+ fmstate->s.conn = NULL;
}
/*
@@ -4056,9 +4471,9 @@ execute_dml_stmt(ForeignScanState *node)
* the desired result. This allows us to avoid assuming that the remote
* server has the same OIDs we do for the parameters' types.
*/
- if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams,
+ if (!PQsendQueryParams(dmstate->s.conn, dmstate->query, numParams,
NULL, values, NULL, NULL, 0))
- pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query);
+ pgfdw_report_error(ERROR, NULL, dmstate->s.conn, false, dmstate->query);
/*
* Get the result, and check for success.
@@ -4066,10 +4481,10 @@ execute_dml_stmt(ForeignScanState *node)
* We don't use a PG_TRY block here, so be careful not to throw error
* without releasing the PGresult.
*/
- dmstate->result = pgfdw_get_result(dmstate->conn, dmstate->query);
+ dmstate->result = pgfdw_get_result(dmstate->s.conn, dmstate->query);
if (PQresultStatus(dmstate->result) !=
(dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true,
+ pgfdw_report_error(ERROR, dmstate->result, dmstate->s.conn, true,
dmstate->query);
/* Get the number of rows affected. */
@@ -5560,6 +5975,40 @@ postgresGetForeignJoinPaths(PlannerInfo *root,
/* XXX Consider parameterized paths for the join relation */
}
+static bool
+postgresIsForeignPathAsyncCapable(ForeignPath *path)
+{
+ return true;
+}
+
+
+/*
+ * Configure waiting event.
+ *
+ * Add wait event so that the ForeignScan node is going to wait for.
+ */
+static bool
+postgresForeignAsyncConfigureWait(ForeignScanState *node, WaitEventSet *wes,
+ void *caller_data, bool reinit)
+{
+ PgFdwScanState *fsstate = GetPgFdwScanState(node);
+
+
+ /* Reinit is not supported for now. */
+ Assert(reinit);
+
+ if (fsstate->s.commonstate->leader == node)
+ {
+ AddWaitEventToSet(wes,
+ WL_SOCKET_READABLE, PQsocket(fsstate->s.conn),
+ NULL, caller_data);
+ return true;
+ }
+
+ return false;
+}
+
+
/*
* Assess whether the aggregation, grouping and having operations can be pushed
* down to the foreign server. As a side effect, save information we obtain in
diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h
index eef410db39..96af75a33e 100644
--- a/contrib/postgres_fdw/postgres_fdw.h
+++ b/contrib/postgres_fdw/postgres_fdw.h
@@ -85,6 +85,7 @@ typedef struct PgFdwRelationInfo
UserMapping *user; /* only set in use_remote_estimate mode */
int fetch_size; /* fetch size for this remote table */
+ bool allow_prefetch; /* true to allow overlapped fetching */
/*
* Name of the relation, for use while EXPLAINing ForeignScan. It is used
@@ -130,6 +131,7 @@ extern void reset_transmission_modes(int nestlevel);
/* in connection.c */
extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt);
+void *GetConnectionSpecificStorage(UserMapping *user, size_t initsize);
extern void ReleaseConnection(PGconn *conn);
extern unsigned int GetCursorNumber(PGconn *conn);
extern unsigned int GetPrepStmtNumber(PGconn *conn);
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index 83971665e3..359208a12a 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -1780,25 +1780,25 @@ INSERT INTO b(aa) VALUES('bbb');
INSERT INTO b(aa) VALUES('bbbb');
INSERT INTO b(aa) VALUES('bbbbb');
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
UPDATE a SET aa = 'zzzzzz' WHERE aa LIKE 'aaaa%';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
UPDATE b SET aa = 'new';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
UPDATE a SET aa = 'newtoo';
-SELECT tableoid::regclass, * FROM a;
+SELECT tableoid::regclass, * FROM a ORDER BY 1, 2;
SELECT tableoid::regclass, * FROM b;
SELECT tableoid::regclass, * FROM ONLY a;
@@ -1840,12 +1840,12 @@ insert into bar2 values(4,44,44);
insert into bar2 values(7,77,77);
explain (verbose, costs off)
-select * from bar where f1 in (select f1 from foo) for update;
-select * from bar where f1 in (select f1 from foo) for update;
+select * from bar where f1 in (select f1 from foo) order by 1 for update;
+select * from bar where f1 in (select f1 from foo) order by 1 for update;
explain (verbose, costs off)
-select * from bar where f1 in (select f1 from foo) for share;
-select * from bar where f1 in (select f1 from foo) for share;
+select * from bar where f1 in (select f1 from foo) order by 1 for share;
+select * from bar where f1 in (select f1 from foo) order by 1 for share;
-- Check UPDATE with inherited target and an inherited source table
explain (verbose, costs off)
@@ -1904,8 +1904,8 @@ explain (verbose, costs off)
delete from foo where f1 < 5 returning *;
delete from foo where f1 < 5 returning *;
explain (verbose, costs off)
-update bar set f2 = f2 + 100 returning *;
-update bar set f2 = f2 + 100 returning *;
+with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1;
+with u as (update bar set f2 = f2 + 100 returning *) select * from u order by 1;
-- Test that UPDATE/DELETE with inherited target works with row-level triggers
CREATE TRIGGER trig_row_before
--
2.18.2
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От: Pavel StehuleДата:
Сообщение: Re: proposal: possibility to read dumped table's name from file