Out of virtual memory on ARM builder

[Richard W.M. Jones]

On Thu, Feb 13, 2014 at 01:47:51PM -0700, Jerry James wrote:
> What do I do about this?
> 
> http://koji.fedoraproject.org/koji/taskinfo?taskID=6526911
> 
> [While building and running tests]:
> 
>     CC   ../build/flintxx/test/t-traits
>     CC   ../build/flintxx/test/t-fmpzxx
> virtual memory exhausted: Cannot allocate memory
> make[1]: *** [../build/flintxx/test/t-fmpzxx] Error 1
> make[1]: Leaving directory `/builddir/build/BUILD/flint-2.4.1/flintxx'
> make: *** [check] Error 2
> 
> The i686 and x86_64 builds were successful.  What can I do to increase the
> likelihood that the ARM build will also complete successfully?  I would
> rather not disable tests if that is not absolutely necessary.

As a general comment, ARM 32 bit has quite limited physical RAM.

Commonly available hardware maxes out at 2 GB.  1 GB or even 512 MB is
not uncommon.  This might be a factor if you expect people to rebuild
your package on their Cubies and Olimexs.

The builders apparently have 4 GB according to a comment in this
thread.  The Calxeda machines I used had 8 GB, the largest I've seen
on ARM.  These use LPAE (which is like PAE on x86), so all that memory
is not available to a single process.

ARM 64 bit will be much better.

Also the ratio of cores to memory can be unusual.  I have an 8 core
ARM 32 bit machine that has 2 GB of RAM, with swap on MMC (very slow),
so you wouldn't want to do a 'make -j8' on it.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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