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From: Aleksander Alekseev <aleksander@tigerdata.com>
Date: Fri, 21 Nov 2025 14:33:38 +0300
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 <CAJ7c6TPC4F9WgaJqcsnGL-cjn7CCopLRew6s9ShNox010G03ug@mail.gmail.com>
Subject: Re: change default default_toast_compression to lz4?
To: pgsql-hackers <pgsql-hackers@postgresql.org>
Cc: Peter Eisentraut <peter@eisentraut.org>
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Hi Peter,

> How about changing the default of default_toast_compression to lz4?

To me it sounds like a great idea.

> I have seen cases where servers had performance problems and were
> CPU-bound because of pglz TOAST compression, and changing it to lz4
> relieved it significantly.  I suspect many users are leaving easy
> performance improvements on the table by not using this option.
>
> The feature was introduced in PostgreSQL 14, so it should be well
> stabilized now.
>
> I suppose one issue is that lz4 support is not compiled-in by default,
> but in practice most users will have it.  The default could be lz4 if
> lz4 support is built, otherwise pglz.  This would be similar to other
> parameters where the default is the best one depending on the build
> configuration.

Are there good reasons why we can't simply make lz4 a required
dependency? In the worst case we could simply copy its implementation,
the license permits.

-- 
Best regards,
Aleksander Alekseev