SuperMicro i7 (UP) - very slow performance

Tom Evans tevans.uk at googlemail.com
Wed Sep 22 14:26:19 UTC 2010


On Wed, Sep 22, 2010 at 2:50 PM, Ian Smith <smithi at nimnet.asn.au> wrote:
> It seems far more than just CPU performance is awry.  Adam's data from
> his i7 shows 2.7 times Bryce's speed for the md5 -t, maybe a lower EST
> rate? - but that could no way account for buildworld taking 22.5 hours.
>
> Recent buildworld (albeit i386) on my Thinkpad T23 ran just shy of 3.5
> hours, without -j on an 1133MHz P3-M, 768MB of 133MHz RAM, 5400rpm UFS
> disk - with X/KDE running meanwhile (~5-7% CPU penalty).
>
> cheers, Ian


md5 -t is quite a small benchmark, even with his misfunctioning CPU it
took <6 seconds to complete.

If his problem is a misapplied heatsink/fan, then his CPU could be
throttling when it gets hot, the hotter it gets the more it throttles,
which could explain his massive buildworld walltime. Perhaps running
something like:

  apply -0 "md5 -t" `jot 10`

would display a notable difference.

Intel chips are quite good at running without much cooling and not
dieing, using thermal throttling to preserve the CPU.

Cheers

Tom


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