Skip to content

pg_test_timing: Show additional TSC clock source debug info#73

Open
lfittl wants to merge 1 commit into
masterfrom
fast-timing-v27
Open

pg_test_timing: Show additional TSC clock source debug info#73
lfittl wants to merge 1 commit into
masterfrom
fast-timing-v27

Conversation

@lfittl
Copy link
Copy Markdown
Owner

@lfittl lfittl commented Apr 10, 2026

No description provided.

In some cases its needed to understand whether TSC frequency data was
sourced from CPUID, and which of the registers. This shows this debug
information at the end of pg_test_timing, through use of a new
pg_timing_tsc_clock_source_info function, replacing the previous
pg_tsc_calibrate_frequency export that was only needed for debug info.

Additionally, emit a warning if TSC frequency from calibration differs
by more than 10% from the TSC frequency in use, suggesting the use
of timing_clock_source = 'system'.

Author: Lukas Fittl <lukas@fittl.com>
Suggested-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/jr4hk2sxhqcfpb67ftz5g4vw33nm67cgf7go3wwmqsafu5aclq%405m67ukuhyszz#2fdfd95b6a4a74410196999818e16cfc
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant