Feedback-ID: i0fe9450f:Fastmail
Date: Tue, 17 Feb 2026 16:26:29 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Andres Freund <andres@anarazel.de>
Cc: Andy Pogrebnoi <andrew.pogrebnoi@percona.com>,
	pgsql-hackers@postgresql.org, Heikki Linnakangas <hlinnaka@iki.fi>,
	Robert Haas <robertmhaas@gmail.com>,
	Thomas Munro <thomas.munro@gmail.com>,
	Matthias van de Meent <boekewurm+postgres@gmail.com>
Subject: Re: Lowering the default wal_blocksize to 4K
Message-ID: <aZQYJcRAunlZLDZY@paquier.xyz>
References: <20231009230805.funj5ipoggjyzjz6@awork3.anarazel.de>
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On Mon, Feb 16, 2026 at 04:13:37PM -0500, Andres Freund wrote:
> On 2026-02-16 10:04:37 +0200, Andy Pogrebnoi wrote:
>> 8Kb XLOG_BLCKSZ
>> =3D=3D=3D=3D
>> Threads          tps        kB_wrtn
>> 1             535.34         207288
>> 5            1457.24         591708
>> 10           1441.85         574700
>> 15            823.98         388732
>>
>> 4Kb XLOG_BLCKSZ
>> =3D=3D=3D=3D
>> Threads          tps        kB_wrtn
>> 1             542.02         153544
>> 5            1556.83         393444
>> 10           1288.00         339648
>> 15            975.32         255708
>=20
> The reduction in bytes written is rather impressive...

It's a pretty nice improvement for a change as simple as that, yes.
+1.
--
Michael

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