Horton

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

Andres Freund <andres@anarazel.de>

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From: Andres Freund <andres@anarazel.de>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Yura Sokolov <y.sokolov@postgrespro.ru>, PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
Date: 2022-09-05T23:09:49Z
Lists: pgsql-hackers 
Hi,

On 2022-08-29 17:26:29 +1200, David Rowley wrote:
> 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 After a bit more revision, mostly updating outdated comments and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.

Responding to Tom's email about guc.c changes [1], I was looking at
MemoryContextContains(). Unless I am missing something, the patch omitted
adjusting that? We'll probably always return false right now.

Probably should have something that tests that MemoryContextContains() works
at least to some degree. Perhaps a test in regress.c?

Greetings,

Andres Freund

[1] https://postgr.es/m/2982579.1662416866%40sss.pgh.pa.us

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