Re: ResourceOwner refactoring

Hello Heikki,

09.11.2023 02:48, Heikki Linnakangas wrote:
>
> Thanks for the testing! Fixed. ...

Thank you for the fix!

Please look at one more failure caused be the new implementation of
ResourceOwners:
numdbs=80
for ((i=1;i<=10;i++)); do
echo "ITERATION $i"

for ((d=1;d<=$numdbs;d++)); do createdb db$d; done

for ((d=1;d<=$numdbs;d++)); do
echo "
create table t(t1 text);
drop table t;
" | psql -d db$d >psql-$d.log 2>&1 &
done
wait
grep 'PANIC' server.log  && break;

for ((d=1;d<=$numdbs;d++)); do dropdb db$d; done
grep 'PANIC' server.log  && break;
done

I could see two failure modes:
2023-11-10 08:42:28.870 UTC [1163274] ERROR:  ResourceOwnerEnlarge called after release started
2023-11-10 08:42:28.870 UTC [1163274] STATEMENT:  drop table t;
2023-11-10 08:42:28.870 UTC [1163274] WARNING:  AbortTransaction while in COMMIT state
2023-11-10 08:42:28.870 UTC [1163274] PANIC:  cannot abort transaction 906, it was already committed

2023-11-10 08:43:27.897 UTC [1164148] ERROR:  ResourceOwnerEnlarge called after release started
2023-11-10 08:43:27.897 UTC [1164148] STATEMENT:  DROP DATABASE db69;
2023-11-10 08:43:27.897 UTC [1164148] WARNING:  AbortTransaction while in COMMIT state
2023-11-10 08:43:27.897 UTC [1164148] PANIC:  cannot abort transaction 1043, it was already committed

The stack trace for the second ERROR (ResourceOwnerEnlarge called ...) is:
...
#6  0x0000558af5b2f35c in ResourceOwnerEnlarge (owner=0x558af716f3c8) at resowner.c:455
#7  0x0000558af5888f18 in dsm_create_descriptor () at dsm.c:1207
#8  0x0000558af5889205 in dsm_attach (h=3172038420) at dsm.c:697
#9  0x0000558af5b1ebed in get_segment_by_index (area=0x558af711da18, index=2) at dsa.c:1764
#10 0x0000558af5b1ea4b in dsa_get_address (area=0x558af711da18, dp=2199023329568) at dsa.c:970
#11 0x0000558af5669366 in dshash_seq_next (status=0x7ffdd5912fd0) at dshash.c:687
#12 0x0000558af5901998 in pgstat_drop_database_and_contents (dboid=16444) at pgstat_shmem.c:830
#13 0x0000558af59016f0 in pgstat_drop_entry (kind=PGSTAT_KIND_DATABASE, dboid=16444, objoid=0) at pgstat_shmem.c:888
#14 0x0000558af59044eb in AtEOXact_PgStat_DroppedStats (xact_state=0x558af7111ee0, isCommit=true) at pgstat_xact.c:88
#15 0x0000558af59043c7 in AtEOXact_PgStat (isCommit=true, parallel=false) at pgstat_xact.c:55
#16 0x0000558af53c782e in CommitTransaction () at xact.c:2371
#17 0x0000558af53c709e in CommitTransactionCommand () at xact.c:306
...

Best regards,
Alexander