P4 Hyperthreading


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Message boards : Number crunching : P4 Hyperthreading

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Majix
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Finland
Message 1068 - Posted: 24 Jun 2004, 9:25:26 UTC

I'm getting some very poor results on a P4C 2.8GHz HT machine:

455 double precision MIPS (Whetstone) per CPU
806 integer MIPS (Dhrystone) per CPU

Even if you double it for 2 logical CPUs it's still very bad. I was thinking, maybe the Boinc client doesn't understand that the two CPUs reported by the OS aren't physical and is doing some very poor load balancing choices causing cache trashing? I don't want to test with Hyperthreading off at the moment, because I can only connect remotely with SSH to the system. Has anyone else done some real HT tests?

Heffed
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Message 1071 - Posted: 24 Jun 2004, 9:32:40 UTC

Yes, hyperthreading is known to confuse the benchmarks.

Benchmark with hyperthreading turned off for more accurate results.

STE\/E [BlackOps]
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Message 1074 - Posted: 24 Jun 2004, 9:42:41 UTC
Last modified: 24 Jun 2004, 11:23:08 UTC

Are you using the latest version of Seti@Home out Majix v3.19, your benchmark score looks more like what a older version would report.

I'm getting between 1700 & 2100 double precision MIPS (Whetstone) per CPU
on my HT PC's depending on how I test it with the v3.19, with or without HT turned on.

Profile DPRGI - Marzio Nieddu
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Message 1079 - Posted: 24 Jun 2004, 10:31:13 UTC

I agree with PoorBoy , your benchmark is very low or you have something that run with BOINC, have you check the taskmanager ?

cheers
SETI@Home ITALIA - Team DPRGI
1° Italian Team in Seti@Home Classic

Message boards : Number crunching : P4 Hyperthreading

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