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From:   Nick Terrell <terrelln@fb.com>
To:     "torvic9@mailbox.org" <torvic9@mailbox.org>
CC:     =?iso-8859-1?Q?Piotr_G=F3rski?= <lucjan.lucjanov@gmail.com>,
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        "masahiroy@kernel.org" <masahiroy@kernel.org>,
        "oleksandr@natalenko.name" <oleksandr@natalenko.name>,
        "michal.lkml@markovi.net" <michal.lkml@markovi.net>
Subject: Re: [PATCH] init: add support for zstd compressed modules
Thread-Topic: [PATCH] init: add support for zstd compressed modules
Thread-Index: AQHXJsw7/R3J18BAv0qAIoSCht+fZqqgCfiA
Date:   Thu, 1 Apr 2021 19:18:24 +0000
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> On Apr 1, 2021, at 12:54 AM, torvic9@mailbox.org wrote:
>=20
> Thanks Piotr, good work!
> Question: Is `-T0` really faster in this particular case than the default=
 `-T1`? Are modules installed sequentially?

The zstd CLI produces deterministic output regardless of the number of thre=
ads used. `-T1` (or not specifying `-T`) will produce the same output as `-=
T0`. `-T0` will be faster for large files (at the default level, multiple j=
obs will be spawned for files > 8MB), and be just as fast as `-T1` for smal=
ler files.

Best,
Nick

> I also saw that Masahiro did some work on modules_install, moving MODULE_=
COMPRESS from the base Makefile to scripts/Makefile.modinst, so perhaps thi=
s should also be moved there at a later point.
>=20
> Tor Vic