From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ludovic =?UTF-8?Q?Court=C3=A8s?= <ludo@gnu.org>
Subject: bug#24937: "deleting unused links" GC phase is too slow
Date: Fri, 17 Apr 2020 10:16:09 +0200
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In-Reply-To: <87eesnmrow.fsf@elephly.net> (Ricardo Wurmus's message of "Thu,
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To: Ricardo Wurmus <rekado@elephly.net>
Cc: 24937@debbugs.gnu.org

Hi Ricardo,

Thanks for running this benchmark!

Ricardo Wurmus <rekado@elephly.net> skribis:

>   root@hydra-guix-127 ~# ls -1 /gnu/store/.links | wc -l
>   2017395

That=E2=80=99s not a lot, my laptop has 2.8M links.

It=E2=80=99s interesting to see that system time remains at ~4.2s in all mo=
des.
So the only thing that modes 2 and 3 achieve is increasing CPU time.
It=E2=80=99s as if the order in which files are stat=E2=80=99d had no impac=
t on I/O
performance.

Ludo=E2=80=99.