Re: Parallel CREATE INDEX for BRIN indexes

Hello Tomas,

14.04.2024 20:09, Tomas Vondra wrote:
> I've pushed this, including backpatching the two fixes. I've reduced the
> amount of data needed by the test, and made sure it works on 32-bits too
> (I was a bit worried it might be sensitive to that, but that seems not
> to be the case).

I've discovered that that test addition brings some instability to the test.
With the following pageinspect/Makefile modification:
-REGRESS = page btree brin gin gist hash checksum oldextversions
+REGRESS = page btree brin $(shell printf 'brin %.0s' `seq 99`) gin gist hash checksum oldextversions

echo "autovacuum_naptime = 1" > /tmp/temp.config
TEMP_CONFIG=/tmp/temp.config make -s check -C contrib/pageinspect
fails for me as below:
...
ok 17        - brin                                      127 ms
not ok 18    - brin                                      140 ms
ok 19        - brin                                      125 ms
...
# 4 of 107 tests failed.

The following change:
-CREATE TABLE brin_parallel_test (a int, b text, c bigint) WITH (fillfactor=40);
+CREATE TEMP TABLE brin_parallel_test (a int, b text, c bigint) WITH (fillfactor=40);
(similar to e2933a6e1) makes the test pass reliably for me.

Best regards,
Alexander