Date: Tue, 20 Jun 2023 14:18:31 -0400
From: Sean O'Grady <sean@thingee.com>
To: pgsql-admin@lists.postgresql.org
Message-ID: <d38e0a7de3bdc933453cf0d893a4294fe1615a19@hey.com>
Subject: Question about wal_compression and what to expect
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Hello,

I've enabled wal_compression however I do not see any change in the 16MB
size for each WAL file. Through all my googling and searching the
mailing lists, I could not find a description if a change *should* be
expected even though many of the articles I've read indicate compression
can save disk space.=C2=A0

I am currently thinking that the records in the WAL file are compressed
for the purpose of writing less data to disk, but that the file is still
padded to 16MB. If so, does that mean to realize a space savings for
archiving that my archive_command should compress the file (gzip, bz2,
etc)?

Thanks,
Sean O'Grady

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      <div class=3D"trix-content">
  <div>Hello,<br><br>I've enabled wal_compression however I do not see any =
change in the 16MB size for each WAL file. Through all my googling and sear=
ching the mailing lists, I could not find a description if a change *should=
* be expected even though many of the articles I've read indicate compressi=
on can save disk space.&nbsp;<br><br>I am currently thinking that the recor=
ds in the WAL file are compressed for the purpose of writing less data to d=
isk, but that the file is still padded to 16MB. If so, does that mean to re=
alize a space savings for archiving that my archive_command should compress=
 the file (gzip, bz2, etc)?<br><br>Thanks,<br>Sean O'Grady</div>
</div>


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