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From: "Frank Ch. Eigler" <fche@redhat.com>
To: Romain GEISSLER <romain.geissler@amadeus.com>
Cc: Mark Wielaard <mark@klomp.org>,
	"elfutils-devel@sourceware.org" <elfutils-devel@sourceware.org>,
	Francois RIGAULT <francois.rigault@amadeus.com>
Subject: Re: Performance issue with systemd-coredump and container process linking 2000 shared libraries.
Date: Wed, 21 Jun 2023 22:40:44 -0400	[thread overview]
Message-ID: <20230622024044.GI5772@redhat.com> (raw)
In-Reply-To: <754003F4-3708-4C9C-AA30-EB76DAECF059@amadeus.com>

Hi -

> On our side Francois also told me this afternoon that he didn’t
> really reproduce the same thing with my reproducer posted here and
> the real systemd-coredump issue he witnessed live, and also noticed
> that with DEBUGINFOD_URLS unset/set to the empty string my
> reproducer has no problem anymore. [...]

Just doing the math from the debuginfod-client point of view (ignoring
other the later systemd side fix that moots this):

For an application that processes these elf/dwarf files sequentially,
queries for each synthetic solib are going to result in 2000 https-404
transactions, sans debuginfod caching.  If you're lucky (reusing a
dwfl object), elfutils may be able to reuse a long-lived https
connection to a server, otherwise a new https connection might have to
be spun up for each.  But even with reuse, we're talking about 2000
pingponging messages.  That will take a handful of minutes of elapsed
time just by itself.

If the calling code made these queries in parallel batches, it would
be much faster overall.

- FChE


  parent reply	other threads:[~2023-06-22  2:40 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-06-14 13:39 Romain Geissler
2023-06-19 15:08 ` Mark Wielaard
2023-06-19 19:56   ` Romain GEISSLER
2023-06-19 20:54     ` Luca Boccassi
2023-06-20 11:59       ` Mark Wielaard
2023-06-20 12:12         ` Luca Boccassi
2023-06-20 13:15     ` Mark Wielaard
2023-06-20 21:37   ` Mark Wielaard
2023-06-20 22:05     ` Romain GEISSLER
2023-06-21 16:24       ` Mark Wielaard
2023-06-21 18:14         ` Romain GEISSLER
2023-06-21 19:39           ` Mark Wielaard
2023-06-22  8:10             ` Romain GEISSLER
2023-06-22 12:03               ` Mark Wielaard
2023-06-27 14:09         ` Mark Wielaard
2023-06-30 16:09           ` Romain GEISSLER
2023-06-30 22:35             ` Mark Wielaard
2023-06-22  2:40       ` Frank Ch. Eigler [this message]
2023-06-22 10:59         ` Mark Wielaard

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