Re: guix-daemon hitting systemd TasksMax

[Joram Schrijver]

Heh, no I'm not. I have to do it with 4 cores + hyperthreading. My first
`guix pull` did have to build many things though, spawning numerous
threads in some cases. I eye-sampled the thread counts during one try
and they were certainly in the hundreds.

I installed Guix from the AUR[1], so I was running the most recent
release. Substitutes were enabled, but almost everything had to be built
instead of downloaded.

[1]: https://aur.archlinux.org/packages/guix/

--
  Joram

On Mon, Apr 18, 2016, at 10:33 PM, Leo Famulari wrote:
> On Sun, Apr 17, 2016 at 12:46:16AM +0200, Ludovic Courtès wrote:
> > 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.
> 
> Joram, are you this lucky? ;)