Re: Reducing the chunk header sizes on all memory context types

David Rowley <dgrowleyml@gmail.com>

From: David Rowley <dgrowleyml@gmail.com>
To: Andres Freund <andres@anarazel.de>
Cc: Robert Haas <robertmhaas@gmail.com>, Yura Sokolov <y.sokolov@postgrespro.ru>, PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
Date: 2022-08-29T05:26:29Z
Lists: pgsql-hackers
On Mon, 29 Aug 2022 at 10:39, David Rowley <dgrowleyml@gmail.com> wrote:
> One more try to make CFbot happy.

After a bit more revision, mostly updating outdated comments and
naming adjustments, I've pushed this.

Per the benchmark results I showed in [1], due to the performance of
having the AllocSet free list pointers stored at the end of the
allocated chunk being quite a bit slower than having them at the start
of the chunk, I adjusted the patch to have them at the start.

Time for me to go and watch the buildfarm results come in.

David

[1] https://postgr.es/m/CAApHDvpuhcPWCzkXZuQQgB8YjPNQSvnncbzZ6pwpHFr2QMMD2w@mail.gmail.com



Commits

  1. Harden memory context allocators against bogus chunk pointers.

  2. Improve our ability to detect bogus pointers passed to pfree et al.

  3. Remove MemoryContextContains().

  4. Remove uses of MemoryContextContains in nodeAgg.c and nodeWindowAgg.c.

  5. Temporarily make MemoryContextContains return false

  6. Make MemoryContextContains work correctly again

  7. Make more effort to put a sentinel at the end of allocated memory

  8. Fix some possibly latent bugs in slab.c

  9. Various cleanups of the new memory context header code

  10. Revert "Add missing padding from MemoryChunk struct"

  11. Use MAXALIGN() in calculations using sizeof(SlabBlock)

  12. Add missing padding from MemoryChunk struct

  13. Improve performance of and reduce overheads of memory management