Hi,
We have developed a PostgreSQL extension and are currently encountering
intermittent crashes related to shared memory on PostgreSQL 17.7. The issue
does not occur everytime, and we have not been able to reliably reproduce it in
our local environment. We have attached the relevant pg logs and backtraces
below for reference.
We also noticed a recent commit addressing a DSM-related issue:
https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=1d0fc2499
Could you please confirm whether this change can resolve the type of crash we
are encountering?
Thanks & Regards,
Reshmithaa B
Member Technical Staff
ZOHO Corporation
[2136038]:ERROR: XX000: dsa_area could not attach to a segment that has been
freed
[2136038]:LOCATION: get_segment_by_index, dsa.c:1781
[2136037]:ERROR: XX000: dsa_area could not attach to a segment that has been
freed
[2136037]:LOCATION: get_segment_by_index, dsa.c:1781
[2018946]:ERROR: XX000: dsa_area could not attach to a segment that has been
freed
[2018946]:CONTEXT: parallel worker
[2018946]:LOCATION: get_segment_by_index, dsa.c:1781
[2018946]:STATEMENT: select sum(enumrowcount)::bigint from <table> where dbid
= <dbid> and table_id != <table_id>
[875575]:LOG: 00000: background worker "parallel worker" (PID 2136037) exited
with exit code 1
[875575]:LOCATION: LogChildExit, postmaster.c:3086
[875575]:LOG: 00000: background worker "parallel worker" (PID 2136038) exited
with exit code 1
[875575]:LOCATION: LogChildExit, postmaster.c:3086
[2061697]:LOG: 00000: Running single-threaded autovacuum for table <table_id>
in database <dbid>
[2061697]:LOCATION: operator(), cstore_vacuum.cpp:267
[875575]:LOG: 00000: server process (PID 2037344) was terminated by signal 11:
Segmentation fault
[875575]:DETAIL: Failed process was running: INSERT INTO <tab>...
[568111]:ERROR: 53200: out of memory
[568111]:DETAIL: Failed on DSA request of size 48.
[568111]:LOCATION: dsa_allocate_extended, dsa.c:811
[568111]:STATEMENT: TRUNCATE TABLE tab3
[495070]:LOG: 00000: Running single-threaded autovacuum for table 269613858 in
database 17266
[495070]:LOCATION: operator(), cstore_vacuum.cpp:267
[568804]:ERROR: 53200: out of memory
[568804]:DETAIL: Failed while allocating entry 2/17266/55068384.
[568804]:LOCATION: pgstat_get_entry_ref, pgstat_shmem.c:510
[568804]:STATEMENT: ANALYZE tab2_temp
[568920]:ERROR: 53200: out of memory
[568920]:DETAIL: Failed on DSA request of size 48.
[568920]:LOCATION: dsa_allocate_extended, dsa.c:811
[568920]:STATEMENT: ANALYZE tab1
[568804]:ERROR: 25P02: current transaction is aborted, commands ignored until
end of transaction block
[568804]:LOCATION: exec_parse_message, postgres.c:1506
[568804]:STATEMENT: delete from tab2 where __ZDBID
in (select __ROWID from tab2_temp)
[568920]:ERROR: 25P02: current transaction is aborted, commands ignored until
end of transaction block
[568920]:LOCATION: exec_parse_message, postgres.c:1506
[568920]:STATEMENT: delete from tab4 where __ZDBID
in (select __ROWID from tab1)
[568111]:ERROR: 53200: out of memory
[568111]:DETAIL: Failed on DSA request of size 48.
[568111]:LOCATION: dsa_allocate_extended, dsa.c:811
[568111]:STATEMENT: select TABLE_ID from Table where TABLE_ID=<id>
[875575]:LOG: 00000: server process (PID 568804) was terminated by signal 11:
Segmentation fault
[875575]:DETAIL: Failed process was running: ROLLBACK
[875575]:LOCATION: LogChildExit, postmaster.c:3108
[875575]:LOG: 00000: terminating any other active server processes
[875575]:LOCATION: HandleChildCrash, postmaster.c:2897
