Re: Changing the state of data checksums in a running cluster

Hello Daniel,

06.04.2026 03:20, Daniel Gustafsson wrote:
> I've pushed fixes for all of these as well as the intermittent failures that
> were seen on some BF animals, and will stare at the buildfarm for a while now.
> So far 10 or so machines have built these green so it looks decent so far.

I've discovered that 006_pgbench_single.pl, 007_pgbench_standby.pl,
008_pitr.pl fail with debug_parallel_query = regress:
echo "debug_parallel_query = regress" > /tmp/temp.config; \
TEMP_CONFIG=/tmp/temp.config PG_TEST_EXTRA="checksum_extended" \
make -s check -C src/test/modules/test_checksums/
...
t/006_pgbench_single.pl .... 13/? # poll_query_until timed out executing this query:
# SELECT setting FROM pg_catalog.pg_settings WHERE name = 'data_checksums';
# expecting this output:
# on
# last actual query output:
# off
# with stderr:
t/006_pgbench_single.pl .... 18/?
#   Failed test 'ensure data checksums are transitioned to on on pgbench_single_main'
#   at .../src/test/modules/test_checksums/t/DataChecksums/Utils.pm line 94.
#          got: '0'
#     expected: '1'
t/006_pgbench_single.pl .... 21/?
#   Failed test 'ensure checksums are set to on on pgbench_single_main'
#   at .../src/test/modules/test_checksums/t/DataChecksums/Utils.pm line 69.
#          got: 'off'
#     expected: 'on'
t/006_pgbench_single.pl .... 45/? # Looks like you failed 2 tests of 47.
t/006_pgbench_single.pl .... Dubious, test returned 2 (wstat 512, 0x200)
Failed 2/47 subtests
t/007_pgbench_standby.pl ... 36/? # die: error running SQL: 'psql:<stdin>:1: ERROR:  failed to start background worker
to process data checksums'
# while running 'psql --no-psqlrc --no-align --tuples-only --quiet --dbname port=19054 host=/tmp/sMj0ywRk6i
dbname='postgres' --file - --variable ON_ERROR_STOP=1' with sql 'SELECT pg_enable_data_checksums(0, 100);
# ' at .../src/test/modules/test_checksums/t/DataChecksums/Utils.pm line 139.
# Looks like your test exited with 29 just after 37.
t/007_pgbench_standby.pl ... Dubious, test returned 29 (wstat 7424, 0x1d00)
All 37 subtests passed
t/008_pitr.pl .............. 2/? # die: error running SQL: 'psql:<stdin>:1: ERROR:  failed to start background worker to
process data checksums'
# while running 'psql --no-psqlrc --no-align --tuples-only --quiet --dbname port=26149 host=/tmp/dLjAB54enA
dbname='postgres' --file - --variable ON_ERROR_STOP=1' with sql 'SELECT pg_enable_data_checksums(0, 100);
# ' at .../src/test/modules/test_checksums/t/DataChecksums/Utils.pm line 139.
# Looks like your test exited with 29 just after 2.
t/008_pitr.pl .............. Dubious, test returned 29 (wstat 7424, 0x1d00)
All 2 subtests passed
t/009_fpi.pl ............... ok
t/010_backup_straddle.pl ... ok
t/011_standby_straddle.pl .. ok

Test Summary Report
-------------------
t/006_pgbench_single.pl  (Wstat: 512 (exited 2) Tests: 47 Failed: 2)
  Failed tests:  18, 22
  Non-zero exit status: 2
t/007_pgbench_standby.pl (Wstat: 7424 (exited 29) Tests: 37 Failed: 0)
  Non-zero exit status: 29
t/008_pitr.pl            (Wstat: 7424 (exited 29) Tests: 2 Failed: 0)
  Non-zero exit status: 29
Files=11, Tests=224, 379 wallclock secs ( 0.07 usr  0.02 sys + 18.55 cusr 38.01 csys = 56.65 CPU)
Result: FAIL

Could you please have a look if this can be fixed?

Best regards,
Alexander