pgsql: Add minimal sleep to stats isolation test functions. - Mailing list pgsql-committers

From Tom Lane
Subject pgsql: Add minimal sleep to stats isolation test functions.
Date
Msg-id E1v1pn0-0002j0-35@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
Add minimal sleep to stats isolation test functions.

The functions test_stat_func() and test_stat_func2() had empty
function bodies, so that they took very little time to run.  This made
it possible that on machines with relatively low timer resolution the
functions could return before the clock advanced, making the test fail
(as seen on buildfarm members fruitcrow and hamerkop).

To avoid that, pg_sleep for 10us during the functions.  As far as we
can tell, all current hardware has clock resolution much less than
that.  (The current implementation of pg_sleep will round it up to
1ms anyway, but someday that might get improved.)

Author: Michael Banck <mbanck@gmx.net>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/68d413a3.a70a0220.24c74c.8be9@mx.google.com
Backpatch-through: 15

Branch
------
REL_18_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/ef18eeeeaea7f64aadf198875670f9d6e56b52df

Modified Files
--------------
src/test/isolation/specs/stats.spec | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)


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