From: "Ludovic Courtès" <ludo@gnu.org>
To: Mark H Weaver <mhw@netris.org>
Cc: guix-devel@gnu.org
Subject: Re: Parallel downloads
Date: Sun, 17 Nov 2019 18:52:13 +0100 [thread overview]
Message-ID: <87sgmmmlv6.fsf@gnu.org> (raw)
In-Reply-To: <87pnhvda3z.fsf@netris.org> (Mark H. Weaver's message of "Wed, 13 Nov 2019 11:16:53 -0500")
Hi Mark,
Mark H Weaver <mhw@netris.org> skribis:
> For these reasons, I'm inclined to think that parallel downloads is the
> wrong approach. If a single download process is not making efficient
> use of the available bandwidth, I'd be more inclined to look carefully
> at why it's failing to do so. For example, I'm not sure if this is the
> case (and don't have time to look right now), but if the current code
> waits until a NAR has finished downloading before asking for the next
> one, that's an issue that could be fixed by use of HTTP pipelining,
> without multiplying the memory usage.
I agree. There’s HTTP pipelining for narinfos but not for nars. Worse,
before fetching a nar, we do a GET /nix-cache-info, and in fact we spawn
a new ‘guix substitute’ process for each download (for “historical
reasons”).
So there’s room for optimization there!
Ludo’.
next prev parent reply other threads:[~2019-11-17 17:52 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-31 15:07 Parallel downloads Pierre Neidhardt
2019-10-31 16:18 ` Tobias Geerinckx-Rice
2019-10-31 16:48 ` Pierre Neidhardt
2019-10-31 18:01 ` zimoun
2019-10-31 18:09 ` Pierre Neidhardt
2019-11-03 14:48 ` Ludovic Courtès
2019-11-03 15:29 ` Pierre Neidhardt
2019-11-06 15:34 ` Ludovic Courtès
2019-11-06 16:08 ` Pierre Neidhardt
2019-11-09 17:40 ` Ludovic Courtès
2019-11-10 13:28 ` Pierre Neidhardt
2019-11-12 15:36 ` Ludovic Courtès
2019-11-12 15:59 ` John Soo
2019-11-12 16:48 ` zimoun
2019-11-13 7:43 ` Efraim Flashner
2019-11-13 11:26 ` zimoun
2019-11-12 17:44 ` Leo Famulari
2019-11-17 17:15 ` Ludovic Courtès
2019-11-13 16:16 ` Mark H Weaver
2019-11-13 18:03 ` Pierre Neidhardt
2019-11-13 18:25 ` Leo Famulari
2019-11-13 19:34 ` Pierre Neidhardt
2019-12-13 9:35 ` Pierre Neidhardt
2019-12-13 12:25 ` Brett Gilio
2019-11-17 17:52 ` Ludovic Courtès [this message]
2019-11-06 21:26 ` Bengt Richter
2019-11-01 10:06 ` Joshua Branson
2019-11-01 19:11 ` Pierre Neidhardt
2019-11-03 14:50 ` Ludovic Courtès
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