Feedback-ID: i0fe9450f:Fastmail
Date: Sat, 11 Mar 2023 08:00:55 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: Tomas Vondra <tomas.vondra@enterprisedb.com>, gkokolatos@pm.me,
	shiy.fnst@fujitsu.com, pgsql-hackers@lists.postgresql.org,
	Rachel Heaton <rachelmheaton@gmail.com>
Subject: Re: Add LZ4 compression in pg_dump
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On Fri, Mar 10, 2023 at 07:05:49AM -0600, Justin Pryzby wrote:
> On Thu, Mar 09, 2023 at 06:58:20PM +0100, Tomas Vondra wrote:
>> I'm a bit confused about the lz4 vs. lz4f stuff, TBH. If we switch to
>> lz4f, doesn't that mean it (e.g. restore) won't work on systems that
>> only have older lz4 version? What would/should happen if we take backup
>> compressed with lz4f, an then try restoring it on an older system where
>> lz4 does not support lz4f?
>=20
> You seem to be thinking about LZ4F as a weird, new innovation I'm
> experimenting with, but compress_lz4.c already uses LZ4F for its "file"
> API.

Note: we already use lz4 frames in pg_receivewal (for WAL) and
pg_basebackup (bbstreamer).
--
Michael

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