pgsql: Reorder FmgrBuiltin members, saving 25% in size. - Mailing list pgsql-committers

From Andres Freund
Subject pgsql: Reorder FmgrBuiltin members, saving 25% in size.
Date
Msg-id E1gCXLG-0006mc-5L@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
Reorder FmgrBuiltin members, saving 25% in size.

That's worth it, as fmgr_builtins is frequently accessed, and as
fmgr_builtins is one of the biggest constant variables in a backend.

On most 64bit systems this will change the size of the struct from
32byte to 24bytes. While that could make indexing into the array
marginally more expensive, the higher cache hit ratio is worth more,
especially because these days fmgr_builtins isn't searched with a
binary search anymore (c.f. 212e6f34d5).

Discussion: https://postgr.es/m/20181016201145.aa2dfeq54rhqzron@alap3.anarazel.de

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/28d750c0cd5b3cea0dfbc84cce24e30f5c2eb966

Modified Files
--------------
src/backend/utils/Gen_fmgrtab.pl | 2 +-
src/include/utils/fmgrtab.h      | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)


pgsql-committers by date:

Previous
From: Tom Lane
Date:
Subject: pgsql: Back off using -isysroot on Darwin.
Next
From: pgsql@postgresql.org
Date:
Subject: pgsql: Tag refs/tags/REL_11_0 was created