From: Bryon Roché <kain@kain.org>
To: Laurenz Albe <laurenz.albe@cybertec.at>
To: Pgsql-admin <pgsql-admin@lists.postgresql.org>
Subject: Re: How to speed WAL apply in destination
Date: Sun, 11 Dec 2022 21:18:06 +0000
Message-ID: <FDCF3710-A2AA-4D39-ACEE-27B979A51878@kain.org> (raw)
In-Reply-To: <44581ceb3c9c96f48e131ed3de33389db07317e9.camel@cybertec.at>
References: <364439211.2445507.1670562179127.ref@mail.yahoo.com>
<364439211.2445507.1670562179127@mail.yahoo.com>
<1E6A35F6-6866-4FDB-8CE8-38C328FF1865@kain.org>
<44581ceb3c9c96f48e131ed3de33389db07317e9.camel@cybertec.at>
On December 9, 2022 10:50:07 AM UTC, Laurenz Albe <laurenz.albe@cybertec.at> wrote:
>On Fri, 2022-12-09 at 08:47 +0000, Bryon Roché wrote:
>>
>> There are fsync parameters which can be set to off that may provide a modest speed increase, at the cost of removing crash safety.
>
>That is spectacularly bad advice.
It is situational advice, and depending on your application, not bad advice at all. It is certainly not something you want off by default, or even regularly.
In fact, the PostgreSQL 15 (and earlier) versions cover this in the documentation for the fsync and synchronous_commit parameters in section 20.5, including considerations involved in deciding when to use those arameters, along with further references in the documentation to cover more of the performance, synchronicity, and durability parameters, in detail.
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To: pgsql-admin@postgresql.org
Cc: kain@kain.org, laurenz.albe@cybertec.at, pgsql-admin@lists.postgresql.org
Subject: Re: How to speed WAL apply in destination
In-Reply-To: <FDCF3710-A2AA-4D39-ACEE-27B979A51878@kain.org>
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