postgres-github.git / summary / log / commit / refs

commit    5ba34f6dc838a1bc4415dc179be5bb2cf3b6d549
Author:   Andres Freund <andres@anarazel.de>
Date:     Sat May 16 15:51:34 2026 +0000

    pg_test_timing: Show additional TSC clock source debug info
    
    In some cases its necessary to understand whether TSC frequency data was
    sourced from CPUID, and which of the registers. Show this debug info at
    the end of pg_test_timing, and rework TSC functions to support that.
    
    This would have helped debug the buildfarm report fixed in 7fc36c5db550
    and is likely going to aid in any TSC-related issues reported during the
    beta period or later.
    
    Additionally, emit a warning if TSC frequency from calibration differs
    by more than 10% from the TSC frequency in use, and suggest the use
    of timing_clock_source = 'system'.
    
    In passing, add an explicit early return in the output function if the
    loop count is zero. This can't happen in practice, but coverity complained
    because we unconditionally call output for the fast TSC measurement.
    
    Author: Lukas Fittl <lukas@fittl.com>
    Suggested-by: Andres Freund <andres@anarazel.de>
    Reviewed-by: Andres Freund <andres@anarazel.de>
    Reviewed-by: Haibo Yan <tristan.yim@gmail.com>
    Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> (coverity fix only)
    Discussion: https://postgr.es/m/CAP53Pkw3Gzb+KTF5pu_o7tzbfZ7+qm2m6uDWuGtTJjZpV9yNpg@mail.gmail.com

[parent: aa1f93a3387a]