Re: pg_stat_bgwriter.buffers_backend is pretty meaningless (and more?)

Andres Freund <andres@anarazel.de> writes:
> Just pushed the actual pg_stat_io view, the splitting of the tablespace test,
> and the pg_stat_io tests.

One of the test cases is flapping a bit:

diff -U3 /home/pg/build-farm-15/buildroot/HEAD/pgsql.build/src/test/regress/expected/stats.out
/home/pg/build-farm-15/buildroot/HEAD/pgsql.build/src/test/regress/results/stats.out
--- /home/pg/build-farm-15/buildroot/HEAD/pgsql.build/src/test/regress/expected/stats.out    2023-03-04
21:30:05.891579466+0100 
+++ /home/pg/build-farm-15/buildroot/HEAD/pgsql.build/src/test/regress/results/stats.out    2023-03-04
21:34:26.745552661+0100 
@@ -1201,7 +1201,7 @@
 SELECT :io_sum_shared_after_reads > :io_sum_shared_before_reads;
  ?column?
 ----------
- t
+ f
 (1 row)

 DROP TABLE test_io_shared;

There are two instances of this today [1][2], and I've seen it before
but failed to note down where.

            regards, tom lane

[1] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=grison&dt=2023-03-04%2021%3A19%3A39
[2] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=mule&dt=2023-03-04%2020%3A30%3A05