Re: Changing shared_buffers without restart

Peter Eisentraut <peter@eisentraut.org>

From: Peter Eisentraut <peter@eisentraut.org>

To: Dmitry Dolgov <9erthalion6@gmail.com>

Cc: pgsql-hackers@postgresql.org

Date: 2024-11-21T07:55:40Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Remove PG_MMAP_FLAGS from mem.h
- c100340729b6 19 (unreleased) landed
Improve runtime and output of tests for replication slots checkpointing.
- 4464fddf7b50 18.0 cited
Revert support for improved tracking of nested queries
- f85f6ab051b7 18.0 cited
Use exported symbols list on macOS for loadable modules as well
- 3feff3916ee1 18.0 cited
Add support for basic NUMA awareness
- 65c298f61fc7 18.0 cited
Avoid unnecessary copying of a string in pg_restore.c
- 5e1915439085 18.0 cited
aio: Infrastructure for io_method=worker
- 55b454d0e140 18.0 cited
Improve InitShmemAccess() prototype
- 2a7b2d97171d 18.0 landed

On 19.11.24 14:29, Dmitry Dolgov wrote:
>> I see that memfd_create() has a MFD_HUGETLB flag.  It's not very clear how
>> that interacts with the MAP_HUGETLB flag for mmap().  Do you need to specify
>> both of them if you want huge pages?
> Correct, both (one flag in memfd_create and one for mmap) are needed to
> use huge pages.

I was worried because the FreeBSD man page says

MFD_HUGETLB	  This flag is currently unsupported.

It looks like FreeBSD doesn't have MAP_HUGETLB, so maybe this is irrelevant.

But you should make sure in your patch that the right set of flags for 
huge pages is passed.