Re: introduce bufmgr hooks

On Thu, Sep 01, 2022 at 05:34:03PM -0700, Andres Freund wrote:
> On 2022-09-01 13:11:50 -0700, Nathan Bossart wrote:
>> On Wed, Aug 31, 2022 at 08:29:31AM -0700, Andres Freund wrote:
>> > I also think it'll
>> > make it harder to improve things in this area, which needs quite a bit of
>> > work.
>>
>> If you have specific refactoring in mind that you think ought to be a
>> prerequisite for this change, I'm happy to give it a try.
>
> There's a few semi-active threads (e.g. about not holding multiple buffer
> partition locks). One important change is to split the way we acquire buffers
> for file extensions - right now we get a victim buffer while holding the
> relation extension lock, because there's simply no API to do otherwise. We
> need to change that so we get acquire a victim buffer before holding the
> extension lock (with the buffer pinned but not [tag] valid), then we need to
> get the extension lock, insert it into its new position in the buffer mapping
> table.

I see, thanks for clarifying.

--
Nathan Bossart
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