To HT or not to HT. That is the question

peterthomas
peterthomas
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Topic 191011

Hi Guys
My new puter is an intel 630 HT enabled.
Currently it crunches a WU in about 6.7 to 6.9 k seconds. But it does two at a time.

I was wondering if disabling HT would make much difference if any.

RandyC
RandyC
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To HT or not to HT. That is the question

Quote:

Hi Guys
My new puter is an intel 630 HT enabled.
Currently it crunches a WU in about 6.7 to 6.9 k seconds. But it does two at a time.

I was wondering if disabling HT would make much difference if any.

The net result is you will be able to do 1 WU in about 55-60% of the time it takes to do two using HT. Resulting in fewer WUs crunched per unit of time.

Seti Classic Final Total: 11446 WU.

networkman
networkman
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Just this week I added a Dell

Just this week I added a Dell Precision 470 workstation to my herd.. it's a dual-core Xeon 2.8 which I chose to enable HT on - so it crunches using 4 threads. :)

I see no reason not to do this.

"Chance is irrelevant. We will succeed."
- Seven of Nine

B52
B52
Joined: 19 Feb 05
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Neither here. Splitting

Neither here.

Splitting the core with HT, will give you an average gain of approx 20%.

The gain will though however only show up SIGNIFICANTLY when using it for something like this (and other) projects. Meaning that some off the code are re-used when running HT and the 2 cores are running the same app.

m.mitch
m.mitch
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Peter, I run all HT PC's

Peter,
I run all HT PC's enabled.

Mike

archae86
archae86
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RE: The gain will though

Message 27281 in response to message 27279

Quote:
The gain will though however only show up SIGNIFICANTLY when using it for something like this (and other) projects. Meaning that some off the code are re-used when running HT and the 2 cores are running the same app.

I beg to differ. It is oft reported that SETI runs much faster when paired with Einstein in a hyperthreaded machine than when paired with another SETI. On my Gallatin the difference is that a typical SETI units consumes 45 CPU minutes when paired with an Einstein run, compared to about 75 CPU minutes when paired with another SETI.

On the other hand, the Einstein half of the pair seems to take the same time in these two cases.

Akos Fekete
Akos Fekete
Joined: 13 Nov 05
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RE: RE: The gain will

Message 27282 in response to message 27281

Quote:
Quote:
The gain will though however only show up SIGNIFICANTLY when using it for something like this (and other) projects. Meaning that some off the code are re-used when running HT and the 2 cores are running the same app.

I beg to differ. It is oft reported that SETI runs much faster when paired with Einstein in a hyperthreaded machine than when paired with another SETI. On my Gallatin the difference is that a typical SETI units consumes 45 CPU minutes when paired with an Einstein run, compared to about 75 CPU minutes when paired with another SETI.

On the other hand, the Einstein half of the pair seems to take the same time in these two cases.

Cache problem. SETI needs the whole cache, but not Einstein.

peterthomas
peterthomas
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Thanks Guys I'll leave it as

Thanks Guys
I'll leave it as is for now.

peterthomas
peterthomas
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Posts: 47
Credit: 23,940
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Hey Mike, How do you get the

Hey Mike,
How do you get the BOINC@AUSTRALIA stats to fold down to two columns. Its a bit tall in the current form in my sig.

thanks
Peter

DanNeely
DanNeely
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his signature is using a

his signature is using a different image name. Specifically his is postfixed with "_banner": http://www.boincstats.com/signature/team_59_banner.gif

m.mitch
m.mitch
Joined: 11 Feb 05
Posts: 187
Credit: 2,188,893
RAC: 2

RE: Hey Mike, How do you

Message 27286 in response to message 27284

Quote:

Hey Mike,
How do you get the BOINC@AUSTRALIA stats to fold down to two columns. Its a bit tall in the current form in my sig.

thanks
Peter

Add the word _banner after the team ID and before the .gif, like so:
http://www.boincstats.com/signature/team_59_banner.gif

Like Dan said.

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