Horton

Re: Large writable variables

Andres Freund <andres@anarazel.de>

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From: Andres Freund <andres@anarazel.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-hackers@postgresql.org, Thomas Munro <thomas.munro@enterprisedb.com>
Date: 2018-10-16T06:22:10Z
Lists: pgsql-hackers 
Hi,

On 2018-10-16 01:49:22 -0400, Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
> > [ let's rearrange the GUC structs ]
> 
> I find it hard to believe that the API breaks you'll cause for extensions
> are a good trade for a few kB reduction in the size of the .data segment.

I'm doubtful that it's worth it too. But more because it seems like a
fair bit of work. I don't think that many extensions use guc_tables.h -
shouldn't most use guc.h, which wouldn't be affected?

Greetings,

Andres Freund

Commits

  1. Apply unconstify() in more places

  2. Improve unconstify() documentation

  3. Drop const cast from dlsym() calls

  4. Const-ify a few more large static tables.

  5. Improve tzparse's handling of TZDEFRULES ("posixrules") zone data.

  6. Avoid statically allocating statement cache in ecpglib/prepare.c.

  7. Reorder FmgrBuiltin members, saving 25% in size.

  8. Add macro to cast away const without allowing changes to underlying type.

  9. Mark constantly allocated dest receiver as const.

  10. Avoid statically allocating formatting.c's format string caches.

  11. Correct constness of system attributes in heap.c & prerequisites.

  12. Avoid statically allocating gmtsub()'s timezone workspace.

  13. Correct constness of a few variables.

  14. Move the replication lag tracker into heap memory.