Re: Keep elog(ERROR) and ereport(ERROR) calls in the cold path

David Rowley <dgrowleyml@gmail.com>

View thread View on postgr.es

From: David Rowley <dgrowleyml@gmail.com>

To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>

Cc: Andres Freund <andres@anarazel.de>, PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>

Date: 2020-09-22T20:42:33Z

Lists: pgsql-hackers

Attachments

tpch_scale5_elog_ereport_cold_v4_vs_master_10min.ods (application/vnd.oasis.opendocument.spreadsheet)

On Tue, 22 Sep 2020 at 19:08, David Rowley <dgrowleyml@gmail.com> wrote:
> I ran another scale=5 TPCH benchmark on v4 against f859c2ffa using gcc
> 9.3. I'm unable to see any gains with this, however, the results were
> pretty noisy. I only ran pgbench for 60 seconds per query. I'll likely
> need to run that a bit longer. I'll do that tonight.

I've attached the results of a TPCH scale=5 run master (f859c2ffa) vs
master + elog_ereport_attribute_cold_v4.patch

It does not look great. The patched version seems to have done about
1.17% less work than master did.

David

Commits

Stop gap fix for __attribute__((cold)) compiler bug in MinGW 8.1
- 687f61634475 14.0 landed
Tidy up definitions of pg_attribute_hot and pg_attribute_cold
- b0727ae99b70 14.0 landed
Fix unportable usage of __has_attribute
- 1fa22a43a56e 14.0 landed
Improve compiler code layout in elog/ereport ERROR calls
- 913ec71d682e 14.0 landed
Define pg_attribute_cold and pg_attribute_hot macros
- 697e1d02f53f 14.0 landed