Re: Offloading acquired build slot loop

[Ludovic Courtès]

Les Harris <address@hidden> skribis:

> In addition I believe I have done all the documented steps like
> generating and authorizing the keys for both the local machine and build
> server and have added the build server to the local machine's
> machines.scm.

Sounds good.  This build server is the only machine listed in
machines.scm, and it really points to a different machine, right?
(Sorry for the dumb L1-support-style question, just to be sure.  ;-))

> When Guix recognizes a build to be performed it appears to start the
> offload. But that process then seems to end up in an endless loop where
> it keeps saying it has acquired a build slot:
>
> ,----
> | process 20852 acquired build slot
> | '/usr/local/var/guix/offload/build.server.com/0'
> | waiting for locks or build slots...
> | process 20852 acquired build slot
> | '/usr/local/var/guix/offload/build.server.com/0'
> | process 20852 acquired build slot
> | '/usr/local/var/guix/offload/build.server.com/0'
> | process 20852 acquired build slot
> | '/usr/local/var/guix/offload/build.server.com/0'
> | process 20852 acquired build slot
> | '/usr/local/var/guix/offload/build.server.com/0'
> `----

The offload hook can reply in 3 different ways when asked for a build
machine: reject (for instance when building for MIPS but machines.scm
doesn’t list any MIPS machine), accept, or postpone (for instance when
there’s one of more matching machine, but it’s currently unreachable or
overloaded.)

The loop here seems to indicate that you’re in the “postpone” situation:
build.server.com matches, but maybe it does not respond when the offload
hook runs “lsh build.server.com cat /proc/loadavg” to estimate its
current load (see ‘machine-load’ in offload.scm.)

Could you double-check whether this command succeeds as root and
non-interactively (no passphrase prompt):

  lsh -l USER build.server.com cat /proc/loadavg

?

TIA!

Ludo’.