bug#48963: "guix build guix" halts after exhausting memory

[Julien Lepiller]

Hi Ludo,

I tried your patch by creating a variant of the guix package. My first attempt was a failure because it's still using almost all my memory and I forgot to enable my swap. In the second attempt, the build phase succeeded, but the build failed during the test phase (test/inferior). I've started a new build hoping it's a non-deterministic failure.

Le 16 juin 2021 16:01:20 GMT-04:00, "Ludovic Courtès" <ludo@gnu.org> a écrit :

Hi,

Julien Lepiller <julien@lepiller.eu> skribis:

 I tried updating my system on my armhf board (2GB of RAM), but during
 "guix system reconfigure", guix tries to build itself (the guix package
 from (gnu packages package-management)). This package uses too much
 memory to build, and I start getting GC warnings like so:

 GC Warning: Out of memory - trying to allocate requested amount (552
 bytes)...
 GC Warning: Header allocation failed: dropping block
 GC Warning: Out of Memory! Heap size: 2571 MiB. Returning NULL!
 Warning: Unwind-only out of memory exception; skipping pre-unwind
 handler.

 after some more progress and a lot more warnings, the build stops (CPU
 is at 2%), but the memory is not freed. The build stayed stuck for a
 long time until I decided to cancel it.

This is ridiculous.  :-/

Can we instead break the build (at the Makefile level) into multiple
smaller chunks, that require less memory, in the same way (guix self)
works?

Yes, that’s a good idea.

Could you check the extent to which the attached patch helps on this
machine?

It doesn’t split as much as (guix self) does, only in three pieces, but
hopefully that helps a bit.  A side effect is that progress report is
now off, but we can fix it later.

Thanks,
Ludo’.