On Thu, 2010-03-18 at 14:57 -0300, Thiago C. Santini wrote:
> We have a computer in our lab we use to run simulations and sometimes
> compiling. It's been working just fine for over 6 months now but
> during the last week we had it's first 3 crashes(only fixable by hard
> restarting the machine). I'm not a very experienced linux user so all
> I tried to do to find out the crash reason was looking into /var/logs
> without any sucess. So I tracked down which programs were being used
> when the crash happened and tried to reproduce the crash.
> So one of the targets was make which I was running using $make -j 32.
> After a few runs trying to make the computer crash again I was able to
> make it crash using $make -j 128
> I'm not sure wheter the reason for the crash is make or gcc but I do
> know it crashes using that command, so I'd like to know if anyone has
> ever had this problem before and how I can get more information about
> the crash that could lead me to the exact crash reason.
> Everything described here happened over ssh though I don't think that
> does make a difference.
You are running on a system with (from what I can tell) 8 processing
threads. So, why are you trying to run at -j32? That's 4 jobs per
processor, plus all the overhead for I/O which is shared between them.
I suspect that when you say "crashed", that the system didn't really
crash. It probably got so bogged down and busy thrashing swap etc. that
it became unresponsive. If the system really did panic then this is a
bug in the kernel (if anywhere), or else maybe you're starting to have a
hardware issue (bad RAM or similar).
In any case, this is not a bug in either make or GCC. If starting that
many jobs causes your system to become unresponsive, then my
recommendation is to not do that :-). Your system is apparently not
powerful enough to support that level of parallelism.