Feedback-ID: ia2694551:Fastmail
Date: Mon, 6 Nov 2023 10:31:41 +0100
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Dilip Kumar <dilipbalaut@gmail.com>
Cc: "Andrey M. Borodin" <x4mmm@yandex-team.ru>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: SLRU optimization - configurable buffer pool and partitioning
 the SLRU lock
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On 2023-Nov-06, Dilip Kumar wrote:

> Yeah so we can see with a small bank size <=16 slots we are seeing
> that the fetching page with hash is 30% slower than the sequential
> search, but beyond 32 slots sequential search is become slower as you
> grow the number of slots whereas with hash it stays constant as
> expected.  But now as you told if keep the lock partition range
> different than the bank size then we might not have any problem by
> having more numbers of banks and with that, we can keep the bank size
> small like 16.  Let me put some more thought into this and get back.
> Any other opinions on this?

dynahash is notoriously slow, which is why we have simplehash.h since
commit b30d3ea824c5.  Maybe we could use that instead.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
"Escucha y olvidarás; ve y recordarás; haz y entenderás" (Confucio)