gpg --list-keys performance [was: Re: GnuPG 2.1.2 making tons of syscalls]

[Daniel Kahn Gillmor]

On Mon 2015-03-30 08:07:38 -0400, Guilhem Moulin wrote:
> On Wed, 25 Feb 2015 at 10:14:20 +0100, Guilhem Moulin wrote:
>>   $ time gpg --homedir /tmp/gnupg1 --list-sigs >/dev/null
>>   1:57.54 (83.55 user, 33.57 sys)  9264k maxres
>>   $ time gpg2 --homedir /tmp/gnupg2 --list-sigs >/dev/null
>>   2:24:34 (564.61 user, 8083.49 sys)  14936k maxres
>> […] 
>> The second timming is really odd: over 2h of system time?  Surely it
>> must be a bug.
>> […]
>>   $ time gpg --homedir /tmp/gnupg1 --list-sigs 0x39278DA8109E6244 >/dev/null
>>   0:17.24 (11.72 user, 5.46 sys)  8852k maxres
>>   $ time gpg2 --homedir /tmp/gnupg2 --list-sigs 0x39278DA8109E6244 >/dev/null
>>   0:30.85 (3.26 user, 27.50 sys)  14564k maxres
>
> Doesn't anyone acknowledge this behavior and the fact that it's a bug?
> I can't believe all these syscalls are intended, somehow.  Incidentally,
> Jesus Cea made a similar observation (with 2.0.27) when updating the
> trustdb:
>
>     http://lists.gnupg.org/pipermail/gnupg-users/2015-March/053343.html

I'm seeing the same behavior you're seeing, and yes, it seems like a
problem.

I also see that you've opened a related bug report here:

 https://bugs.g10code.com/gnupg/issue1710

maybe it would be good to file separate bug reports for each specific
issue so we can track them down?  the TL;DR of your initial post had a
number of good independent details.

Have you tried profiling the extremely slow invocations with "valgrind
--tool=callgrind" ?  that might yield some hints about where to start
fixing the problem.

       --dkg