Date: Wed, 21 Jun 2023 13:32:13 -0400
From: Sean O'Grady <sean@thingee.com>
To: Jeff Janes <jeff.janes@gmail.com>,
 Scott Ribe <scott_ribe@elevated-dev.com>
Cc: "pgsql-admin@lists.postgresql.org" <pgsql-admin@lists.postgresql.org>,
 "Wetmore, Matthew (CTR)" <matthew.wetmore@express-scripts.com>
Message-ID: <c36c4be478c2b271600a58281711e4add367d136@hey.com>
In-Reply-To: 
 <CAMkU=1zR+w=Zjh_UKTs5hnD5LMRK0ct1uhZ6p3zNFmE_V_oYtw@mail.gmail.com>
Subject: Re: Question about wal_compression and what to expect
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> The internal compression has to compress each record in isolation,
> which is not nearly as good as compressing the entire file as there
> are patterns that exist between records not just within records.

I see, that's makes sense. My sense is that wal_compression is really
first to alleviate disk IO pressure and secondarily as a space saving
benefit. Since I've set about archive_timeout because of a relatively
light workload, I probably shouldn't need to worry about IO issues...

Thanks,
Sean

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  <blockquote>The internal compression has to compress each record in isola=
tion, which is not nearly as good as compressing the entire file as there a=
re patterns that exist between records not just within records.</blockquote=
><div><br>I see, that's makes sense. My sense is that wal_compression is re=
ally first to alleviate disk IO pressure and secondarily as a space saving =
benefit. Since I've set about archive_timeout because of a relatively light=
 workload, I probably shouldn't need to worry about IO issues...<br><br>Tha=
nks,<br>Sean</div>
</div>


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