Re: Reducing the chunk header sizes on all memory context types - Mailing list pgsql-hackers

Em ter., 4 de out. de 2022 às 05:36, David Rowley <dgrowleyml@gmail.com> escreveu:

On Tue, 4 Oct 2022 at 13:35, Ranier Vilela <ranier.vf@gmail.com> wrote:
> Revisiting my work on reducing memory consumption, I found this patch left out.
> I'm not sure I can help.
> But basically I was able to write and read the block size, in the chunk.
> Could it be the case of writing and reading the context pointer in the same way?
> Sure this leads to some performance loss, but would it make it possible to get the context pointer from the chunk?
> In other words, would it be possible to save the context pointer and compare it later in MemoryContextContains?

I'm not really sure I understand the intention of the patch. The
header size for all our memory contexts was already reduced in
c6e0fe1f2.  The patch you sent seems to pre-date that commit.

There is zero intention to commit this. It's just an experiment I did.

As it is in the patch, it is possible to save the context pointer outside the header chunk.

Making it possible to retrieve it in MemoryContextContains.