Message-ID: <783426a05a756b29b5b1ef4d5640f22d999fdec8.camel@j-davis.com>
Subject: Re: Use WALReadFromBuffers in more places
From: Jeff Davis <pgsql@j-davis.com>
To: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Cc: Jingtang Zhang <mrdrivingduck@gmail.com>,
 pgsql-hackers@lists.postgresql.org, Nitin Jadhav
 <nitinjadhavpostgres@gmail.com>
Date: Wed, 24 Sep 2025 11:27:43 -0700
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On Wed, 2025-09-24 at 07:26 -0700, Bharath Rupireddy wrote:
> Right. Reading unflushed WAL buffers for replication was one of the
> motivations. But, in general, WALReadFromBuffers has more benefits
> since it lets WAL buffers act as a cache for reads, avoiding the need
> to re-read WAL from disk for (both physical and logical) replication.
> For example, it makes the use of direct I/O for WAL more realistic
> and
> can provide significant performance benefits [1].

Is it possible to do a POC that shows the potential benefit, or are we
still too far away?

Regards,
	Jeff Davis