Обсуждение: Opclass parameters of indexes lost after REINDEX CONCURRENTLY
Hi all, While reviewing the code for opclass parameters with indexes, I have noticed that opclass parameters are lost after a concurrent reindex. As we use a IndexInfo to hold the information of the new index when creating a copy of the old one, it is just a matter of making sure that ii_OpclassOptions is filled appropriately, but that was missed by 911e702. Attached is a patch to fix the issue. After a concurrent reindex, we would not finish with a corrupted index, just with one rebuilt with default opclass parameter values. Any objections or comments? -- Michael
Вложения
On Sat, Oct 30, 2021 at 1:28 AM Michael Paquier <michael@paquier.xyz> wrote:
Hi all,
While reviewing the code for opclass parameters with indexes, I have
noticed that opclass parameters are lost after a concurrent reindex.
As we use a IndexInfo to hold the information of the new index when
creating a copy of the old one, it is just a matter of making sure
that ii_OpclassOptions is filled appropriately, but that was missed by
911e702.
Attached is a patch to fix the issue. After a concurrent reindex, we
would not finish with a corrupted index, just with one rebuilt with
default opclass parameter values.
Any objections or comments?
--
Michael
Hi,
+ newInfo->ii_NumIndexAttrs);
It seems we may not need to allocate these many entries (as shown by the concur_appclass_ind_2 example in the test).
In the previous loop (starting line 1359), we can increment a counter which would finally tell us how many oldInfo->ii_OpclassOptions[i] is not NULL.
Then that many entries can be allocated in the above code.
Cheers
On Sat, Oct 30, 2021 at 3:59 AM Zhihong Yu <zyu@yugabyte.com> wrote:
On Sat, Oct 30, 2021 at 1:28 AM Michael Paquier <michael@paquier.xyz> wrote:Hi all,
While reviewing the code for opclass parameters with indexes, I have
noticed that opclass parameters are lost after a concurrent reindex.
As we use a IndexInfo to hold the information of the new index when
creating a copy of the old one, it is just a matter of making sure
that ii_OpclassOptions is filled appropriately, but that was missed by
911e702.
Attached is a patch to fix the issue. After a concurrent reindex, we
would not finish with a corrupted index, just with one rebuilt with
default opclass parameter values.
Any objections or comments?
--
MichaelHi,+ newInfo->ii_OpclassOptions = palloc0(sizeof(Datum) *+ newInfo->ii_NumIndexAttrs);It seems we may not need to allocate these many entries (as shown by the concur_appclass_ind_2 example in the test).In the previous loop (starting line 1359), we can increment a counter which would finally tell us how many oldInfo->ii_OpclassOptions[i] is not NULL.Then that many entries can be allocated in the above code.Cheers
Hi,
Upon further look, my previous comment was premature. Please ignore that.
+ newInfo->ii_OpclassOptions[i] = oldInfo->ii_OpclassOptions[i];
Should datumCopy() be used inside the loop ? I saw the following in get_attoptions(Oid relid, int16 attnum):
result = datumCopy(attopts, false, -1); /* text[] */
Cheers
On Sat, Oct 30, 2021 at 04:11:06AM -0700, Zhihong Yu wrote: > Should datumCopy() be used inside the loop ? I saw the following > in get_attoptions(Oid relid, int16 attnum): Yeah, you are right that it would be better here to use get_attoptions() to grab a copy of each attribute's option directly from the catalogs. We also do that for predicates and expressions. -- Michael
Вложения
On Sat, Oct 30, 2021 at 09:26:35PM +0900, Michael Paquier wrote: > Yeah, you are right that it would be better here to use > get_attoptions() to grab a copy of each attribute's option directly > from the catalogs. We also do that for predicates and expressions. While looking again at this one this morning, I have extended the tests with more columns and some default values, then applied the patch by using get_attoptions() to grab each attribute's options as of add5cf2. Predicates and expressions are grabbed through the syscache, so that's just more consistent. -- Michael