Processor contention(?) and network bandwidth on AMD
jlb17 at duke.edu
Mon Apr 29 12:49:32 PDT 2002
On Mon, 29 Apr 2002 at 3:40pm, Mark Hahn wrote
> well, there are several contributing factors, which are probably
> mitigated by running a decently modern (ie 2.4.18) kernel.
> for instance, at gigabit speeds, you're almost certainly generating
> nontrivial MM load. there's been a huge amount of improvement in 2.4's
> in how they handle ram.
These tests (obviously) were only at FE speed, though. The receiving end
was gigabit, but the sending end (the dual AMD nodes) was FE.
> > unloaded: 11486.6 KB/real sec
> > 2 matlab simulations: 10637.8 KB/real sec
> > 2 matlab simulations and 2 SETI at homes (nice -19): 6645.4 KB/real sec
> SETI at home is obviously in the "so don't do that" category. I expect your
> matlab was decelerated by a similar amount.
Sure, but it was just an example of a niced background load, which
"shouldn't" interfere with anything. It certainly shouldn't crash
bandwidth like that.
> > tested (dual PIII 933 on an i860) showed very little bandwidth drop with
> i860 is a P4 chipset afaik...
Oops -- not enough coffee. I meant i840. Dual PIII with RDRAM.
Department of Biomedical Engineering
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