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From: "David G. Johnston" <david.g.johnston@gmail.com>
Date: Fri, 27 Feb 2026 07:36:14 -0700
Message-ID: <CAKFQuwb9B85khromJGFTxdbAOTBgRFdOXKgiXMYytttSbw9EMw@mail.gmail.com>
Subject: Re: Change WAL directory via conf
To: Thomas Butz <tbutz@optitool.de>
Cc: "pgsql-general@lists.postgresql.org" <pgsql-general@lists.postgresql.org>
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On Friday, February 27, 2026, Thomas Butz <tbutz@optitool.de> wrote:

> Is there a reason why the location of the WAL directory cannot be
> specified via the configuration?
> The documentation describes a workaround using a symbolic link, which I
> find rather awkward:
>
> https://www.postgresql.org/docs/current/wal-internals.html
>
> Why is there no wal_directory analogous to data_directory?
>

WAL is data in the sense of what data_directory covers.  Both it and the
main files can be placed outside the physical directory so long as those
external locations can be navigated to by symbolic links.  The fact initdb
provides for this means it=E2=80=99s supported just fine.  Just no one has =
bothered
to make a server program to perform that same work post-initdb.  An SQL
command is not possible though, we aren=E2=80=99t going to be able to move =
WAL
while the server is running for hopefully self-evident reasons.

David J.

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On Friday, February 27, 2026, Thomas Butz &lt;<a href=3D"mailto:tbutz@optit=
ool.de">tbutz@optitool.de</a>&gt; wrote:<br><blockquote class=3D"gmail_quot=
e" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">=
Is there a reason why the location of the WAL directory cannot be specified=
 via the configuration?<br>
The documentation describes a workaround using a symbolic link, which I fin=
d rather awkward:<br>
<br>
<a href=3D"https://www.postgresql.org/docs/current/wal-internals.html" targ=
et=3D"_blank">https://www.postgresql.org/<wbr>docs/current/wal-internals.<w=
br>html</a><br>
<br>
Why is there no wal_directory analogous to data_directory?<br>
</blockquote><div><br></div><div>WAL is data in the sense of what data_dire=
ctory covers.=C2=A0 Both it and the main files can be placed outside the ph=
ysical directory so long as those external locations can be navigated to by=
 symbolic links.=C2=A0 The fact initdb provides for this means it=E2=80=99s=
 supported just fine.=C2=A0 Just no one has bothered to make a server progr=
am to perform that same work post-initdb.=C2=A0 An SQL command is not possi=
ble though, we aren=E2=80=99t going to be able to move WAL while the server=
 is running for hopefully self-evident reasons.</div><div><br></div><div>Da=
vid J.</div><div><br></div>

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