From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: Performance issues with /gnu/store in virtual machines
Date: Tue, 22 Aug 2017 12:11:43 +0200
Message-ID: <87shgj7vz4.fsf@gnu.org>
References: <20170817210547.3fafde57@cbaines.net>
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In-Reply-To: <20170817210547.3fafde57@cbaines.net> (Christopher Baines's
	message of "Thu, 17 Aug 2017 21:05:47 +0100")
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To: Christopher Baines <mail@cbaines.net>
Cc: help-guix@gnu.org

Hi Chris,

Christopher Baines <mail@cbaines.net> skribis:

>   1.13    0.000019           0      3853           openat

[...]

>  13.56    0.193014          50      3853           openat

So openat(2) is 4 orders of magnitude slower in the VM, which is a
problem.

I guess a large part of that is due to the fact that VM created with
=E2=80=98guix system vm=E2=80=99 use unionfs as their root file system, whi=
ch is a FUSE
thing (see the =E2=80=9Cvolatile=E2=80=9D options in (gnu system vm), (gnu =
system
linux-initrd), and (gnu build linux-boot).)  I=E2=80=99m not sure how we co=
uld
avoid it.

Can you confirm that the same =E2=80=98find=E2=80=99 command is faster in a=
 full-blown
=E2=80=9Cguix system disk-image=E2=80=9D VM?

Thanks,
Ludo=E2=80=99.