[Numpy-discussion] custom atlas

[Charles R Harris]

On Tue, Jul 5, 2011 at 8:37 AM, Charles R Harris
<charlesr.harris at gmail.com>wrote:

>
>
> On Tue, Jul 5, 2011 at 8:13 AM, Neal Becker <ndbecker2 at gmail.com> wrote:
>
>> Charles R Harris wrote:
>>
>> > On Tue, Jul 5, 2011 at 7:45 AM, Neal Becker <ndbecker2 at gmail.com>
>> wrote:
>> >
>> >> I thought I'd try to speed up numpy on my fedora system by rebuilding
>> the
>> >> atlas
>> >> package so it would be tuned for my machine.  But when I do:
>> >>
>> >> rpmbuild -ba -D 'enable_native_atlas 1' atlas.spec
>> >>
>> >> it fails with:
>> >>
>> >> res/zgemvN_5000_100 : VARIATION EXCEEDS TOLERENCE, RERUN WITH HIGHER
>> REPS.
>> >>
>> >> A bit of googling has not revealed a solution.  Any hints?
>> >>
>> >>
>> >>
>> > I've never seen that, OTOH, I haven't built ATLAS in the last few years.
>> Do
>> > you have all the power saving/frequency changing options turned off?
>> What
>> > version of ATLAS are you using? What CPU?
>> >
>> > Chuck
>>
>> Ah, hadn't tried turing off cpuspeed.  Try again... nope same error.
>>
>> 2 cpus, each:
>> model name      : Intel(R) Core(TM)2 Duo CPU     T7500  @ 2.20GHz
>> stepping        : 11
>> cpu MHz         : 800.000  << that's what it says @idle
>>
>
> You haven't got cpu frequency scaling under control. Linux? Depending on
> the distro you can write to a file in /sys (for each cpu) or run a program
> to make the setting, or click on a panel applet. Sometimes the scaling is
> set in the bios also. Google is your friend here. I have
>
> $charris at f13 ~$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
> ondemand
>
> And what you want to see is performance instead of ondemand.
>
>
Here's some good info <http://tinyurl.com/o8o7b>.

Chuck
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/numpy-discussion/attachments/20110705/1b7ed28e/attachment.html>