From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Soo <jsoo1@asu.edu>
Subject: Re: Parallel downloads
Date: Tue, 12 Nov 2019 07:59:44 -0800
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To: =?utf-8?Q?Ludovic_Court=C3=A8s?= <ludo@gnu.org>
Cc: guix-devel@gnu.org

Hi everyone,

I=E2=80=99ve been watching this from afar and one thing and while I have to a=
gree with this:

> .. I suspect there=E2=80=99s little to
> be gained by having several connections in parallel.

I do have to say that more fine grained concurrency would really help speed u=
p builds without substitutes.

 Especially on old hardware, some builds can actually exhaust all resources.=
 That means you can=E2=80=99t really get a speed up by bumping the max jobs.=
=20

What would help is doing downloads of sources and substitutes asynchronously=
 while a non-substitute job is taking place. If some network activity could b=
e backgrounded, I think you might find build times decrease a lot.=20

Thanks!

John