On 09/05/2016 03:58 PM, Steve Singer wrote:
> On 08/31/2016 04:51 PM, Petr Jelinek wrote:
>> Hi,
>>
>> and one more version with bug fixes, improved code docs and couple
>> more tests, some general cleanup and also rebased on current master
>> for the start of CF.
>>
>>
>>
>
A few more things I noticed when playing with the patches
1, Creating a subscription to yourself ends pretty badly,
the 'CREATE SUBSCRIPTION' command seems to get stuck, and you can't kill
it. The background process seems to be waiting for a transaction to
commit (I assume the create subscription command). I had to kill -9 the
various processes to get things to stop. Getting confused about
hostnames and ports is a common operator error.
2. Failures during the initial subscription aren't recoverable
For example
on db1 create table a(id serial4 primary key,b text); insert into a(b) values ('1'); create publication testpub for
tablea;
on db2 create table a(id serial4 primary key,b text); insert into a(b) values ('1'); create subscription testsub
connection'host=localhost port=5440
dbname=test' publication testpub;
I then get in my db2 log
ERROR: duplicate key value violates unique constraint "a_pkey"
DETAIL: Key (id)=(1) already exists.
LOG: worker process: logical replication worker 16396 sync 16387 (PID
10583) exited with exit code 1
LOG: logical replication sync for subscription testsub, table a started
ERROR: could not crate replication slot "testsub_sync_a": ERROR:
replication slot "testsub_sync_a" already exists
LOG: worker process: logical replication worker 16396 sync 16387 (PID
10585) exited with exit code 1
LOG: logical replication sync for subscription testsub, table a started
ERROR: could not crate replication slot "testsub_sync_a": ERROR:
replication slot "testsub_sync_a" already exists
and it keeps looping.
If I then truncate "a" on db2 it doesn't help. (I'd expect at that point
the initial subscription to work)
If I then do on db2 drop subscription testsub cascade;
I still see a slot in use on db1
select * FROM pg_replication_slots ; slot_name | plugin | slot_type | datoid | database | active |
active_pid | xmin | catalog_xmin | rest
art_lsn | confirmed_flush_lsn
----------------+----------+-----------+--------+----------+--------+------------+------+--------------+-----
--------+--------------------- testsub_sync_a | pgoutput | logical | 16384 | test | f
| | | 1173 | 0/15
66E08 | 0/1566E40