Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?

vignesh C <vignesh21@gmail.com>

From: vignesh C <vignesh21@gmail.com>

To: David Geier <geidav.pg@gmail.com>

Cc: Lukas Fittl <lukas@fittl.com>, Michael Paquier <michael@paquier.xyz>, Ibrar Ahmed <ibrar.ahmad@gmail.com>, Maciek Sakrejda <m.sakrejda@gmail.com>, Andres Freund <andres@anarazel.de>, pgsql-hackers <pgsql-hackers@postgresql.org>

Date: 2023-01-14T06:58:44Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

pg_test_timing: Also test RDTSC[P] timing, report time source, TSC frequency
- 16fca4825483 19 (unreleased) landed
Allow retrieving x86 TSC frequency/flags from CPUID
- bcb2cf41f964 19 (unreleased) landed
instrumentation: Standardize ticks to nanosecond conversion method
- 0022622c93d9 19 (unreleased) landed
instrumentation: Use Time-Stamp Counter on x86-64 to lower overhead
- 294520c44487 19 (unreleased) landed
Zero initialize uses of instr_time about to trigger compiler warnings
- 25b2aba0c3a5 16.0 landed
instr_time: Represent time as an int64 on all platforms
- 03023a2664f8 16.0 landed
Add 250c8ee07ed to git-blame-ignore-revs
- ff23b592ad66 16.0 cited

On Wed, 4 Jan 2023 at 17:32, David Geier <geidav.pg@gmail.com> wrote:
>
> I fixed the compilation error on CFBot.
> I missed adding instr_time.c to the Meson makefile.
> New patch set attached.

The patch does not apply on top of HEAD as in [1], please post a rebased patch:
=== Applying patches on top of PostgreSQL commit ID
ff23b592ad6621563d3128b26860bcb41daf9542 ===
=== applying patch
./0002-Use-CPU-reference-cycles-via-RDTSC-to-measure-time-v6.patch
....
patching file src/tools/msvc/Mkvcbuild.pm
Hunk #1 FAILED at 135.
1 out of 1 hunk FAILED -- saving rejects to file src/tools/msvc/Mkvcbuild.pm.rej

[1] - http://cfbot.cputube.org/patch_41_3751.log

Regards,
Vignesh