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Subject: Re: WAL & ZFS
From: Rui DeSousa <rui@crazybean.net>
In-Reply-To: <FC215502-166A-49DB-B3DA-D08727A34C0B@elevated-dev.com>
Date: Thu, 31 Mar 2022 17:32:58 -0400
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Precedence: bulk

I would recommend a separate pg_wal filesystem with the record size to =
match the WAL page size; in my case 16k.  I have keep the default record =
size at 128k for the data volume and that configuration has worked well =
for supporting large DSS while using 16k data blocks.

> On Mar 30, 2022, at 5:32 PM, Scott Ribe <scott_ribe@elevated-dev.com> =
wrote:
>=20
> I've read all the info I could find re running PG on ZFS: turn off =
full page writes, turn on lz4, tweak recordsize so as to take advantage =
of compression, etc. One thing I haven't seen is whether a separate =
volume for WAL would benefit from a larger recordsize. Or any other =
tweaks???
>=20
> --
> Scott Ribe
> scott_ribe@elevated-dev.com
> https://www.linkedin.com/in/scottribe/
>=20
>=20
>=20
>=20
>=20