Re: [Ceph-maintainers] Bug#849657: ceph: FTBFS on mips(el): g++: virtual memory exhausted: Cannot allocate memory

Aurelien Jarno <[email protected]> Thu, 5 Jan 2017 21:16:57 +0100

Newsgroups	gmane.linux.debian.ports.mips
Message-ID	<[email protected]>

On 2017-01-05 14:00, Gaudenz Steinlin wrote:
> 
> Hi
> 
> Aurelien Jarno <[email protected]> writes:
> 
> > On 2016-12-30 10:06, Emilio Pozuelo Monfort wrote:
> >> On 29/12/16 20:56, Gaudenz Steinlin wrote:
> >
> > The problem is indeed a memory issue, not that the buildd doesn't have
> > enough memory, but just that you can allocate only 2GB per process on a
> > 32-bit MIPS machine. As Emilio said, the above GCC flag should help to
> > reduce the memory usage by running the garbage collector more often.
> >
> > However gcc 6.3 seems to have improved the situation a bit, so I given
> > back the packages, I hope they will build now. Otherwise I have a patch
> > ready to change the GCC defaults. That said GCC upstream consider it's a
> > bug in the garbage collector [1], so that should be fixed instead and the
> > patch should be considered as a temporary workaround.
> >
> 
> Aurelien thanks for taking care and resheduling the build. Unfortunately
> this did not solve the problem. But setting the following variables
> solves the virtual memory issue for me on the mipsel porterbox (eller):
> 
> export DEB_CFLAGS_MAINT_APPEND= --param ggc-min-expand=10 -O1
> export DEB_CXXFLAGS_MAINT_APPEND= --param ggc-min-expand=10 -O1
> export DEB_CFLAGS_MAINT_STRIP= -O2
> export DEB_CXXFLAGS_MAINT_STRIP= -O2

Thanks for testing that.

I have found that the issue is also workarounded by keeping -O2 and
--param ggc-min-expand=5, which is a quite aggressive value. The patch I
have for GCC reduced the value to 30 (which corresponds to disabling the
heuristics). Also note that the build failure actually only concern the
testsuite, the code itself builds without any change.

I'll report the bug to upstream with the preprocessed source as I have
been advised.

Aurelien

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
[email protected]                 http://www.aurel32.net

signature.asc (application/pgp-signature, 833 B)