Date: Mon, 6 Oct 2025 21:38:03 +0000 (UTC)
From: Thomas Carroll <tomfecarroll@yahoo.com>
To: Pgsql-admin <pgsql-admin@lists.postgresql.org>,
	Raj <rajeshkumar.dba09@gmail.com>
Message-ID: <469228369.58843.1759786683881@mail.yahoo.com>
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 <CAJk5AtbaQYshqms+AnVn0A_BOHFjfYhdEaAsLGWf0zVnA_5N7Q@mail.gmail.com>
References: 
 <CAJk5AtbaQYshqms+AnVn0A_BOHFjfYhdEaAsLGWf0zVnA_5N7Q@mail.gmail.com>
Subject: Re: Wal_keep_size
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 Hope nobody minds me chipping in here.
The answer is "not necessarily."=C2=A0 The names make them seem closely rel=
ated, but not so much.
max_wal_size is all about checkpoints.=C2=A0 When the WAL exceeds this, Pos=
tgres will try to run a checkpoint.=C2=A0 Under some circumstances it won't=
, but let's keep it simple for now.
wal_keep_size is all about replication.=C2=A0 Replicas need WAL files to st=
ick around for long enough that they can process them.=C2=A0 wal_keep_size =
is a minimum figure.
Tom    On Monday, October 6, 2025 at 03:51:17 PM EDT, Raj <rajeshkumar.dba0=
9@gmail.com> wrote: =20
=20
 Should Wal_keep_size <=3D max_wal_size ? =20
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        <div dir="ltr" data-setdir="false">Hope nobody minds me chipping in here.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">The answer is "not necessarily."&nbsp; The names make them seem closely related, but not so much.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">max_wal_size is all about <i>checkpoints</i>.&nbsp; When the WAL exceeds this, Postgres will try to run a checkpoint.&nbsp; Under some circumstances it won't, but let's keep it simple for now.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">wal_keep_size is all about <i>replication</i>.&nbsp; Replicas need WAL files to stick around for long enough that they can process them.&nbsp; wal_keep_size is a minimum figure.</div><div><br></div><div dir="ltr" data-setdir="false">Tom</div>
        
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                        On Monday, October 6, 2025 at 03:51:17 PM EDT, Raj &lt;rajeshkumar.dba09@gmail.com&gt; wrote:
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                <div><div id="yiv6056229186"><div>Should Wal_keep_size &lt;= max_wal_size ?</div>
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