Date: Sun, 11 Dec 2022 21:18:06 +0000
From: =?ISO-8859-1?Q?Bryon_Roch=E9?= <kain@kain.org>
To: Laurenz Albe <laurenz.albe@cybertec.at>,
 Pgsql-admin <pgsql-admin@lists.postgresql.org>
Subject: Re: How to speed WAL apply in destination
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On December 9, 2022 10:50:07 AM UTC, Laurenz Albe <laurenz=2Ealbe@cybertec=
=2Eat> wrote:
>On Fri, 2022-12-09 at 08:47 +0000, Bryon Roch=C3=A9 wrote:
>>
>> There are fsync parameters which can be set to off that may provide a m=
odest speed increase, at the cost of removing crash safety=2E
>
>That is spectacularly bad advice=2E

It is situational advice, and depending on your application, not bad advic=
e at all=2E It is certainly not something you want off by default, or even =
regularly=2E

In fact, the PostgreSQL 15 (and earlier) versions cover this in the docume=
ntation for the fsync and synchronous_commit parameters in section 20=2E5, =
including considerations involved in deciding when to use those arameters, =
along with further references in the documentation to cover more of the per=
formance, synchronicity, and durability parameters, in detail=2E