Re: guix-daemon hitting systemd TasksMax

[Ludovic Courtès]

Leo Famulari <address@hidden> skribis:

> On Sat, Apr 16, 2016 at 03:12:15PM +0200, Joram Schrijver wrote:
>> I am running Arch Linux, also with systemd 229. It doesn't look like
>> Debian applies any patches to systemd, so our installations should
>> pretty much be the same.
>> 
>> Perhaps the limit is only reached during the build process of some
>> specific packages?
>
> `guix pull` usually doesn't build any packages, but sometimes it does
> need to. My (limited) understanding is that it sometimes needs to build
> (or download) updated dependencies of Guix itself.
>
> Do you think the number of "Tasks" would increase with more cores? I
> only have 4 cores on my machines. Maybe if you had more, the builders
> spawned by your guix-daemon would run more tasks as a consequence of
> using all the cores.

Right, ‘guix pull’ entails a build of Guix using as many cores as
possible, with one process per core (and I think each Guile has two
threads, one of which is the signal delivery thread.)

So, if the limit on the total number of threads + processes is 512 and
you have 256 cores or more (lucky you!), you may hit the limit.

Ludo’.