F@H: HT Question

[BlackMountainCow]

Hey!

I decided to give F@H some CPU time again. I was just wondering, if two CLI instances are faster than just one, especially as I see a "use 100% CPU" setting in the latest F@H CLI. Any experiences here? Do 2 WUs just take twice as long as one and thus there's no difference or is there a gain in running 2 instances at the same time. Pentium 4 2.8 HT.


:beer:

thx

 

[Wolfsraider]

BMC you will definately get more by using ht and running 2 instances.

The newest v5 client offers service installs during the install.

Hope this Helps

Mike

Edit:

For a complete install guide and more answers -- Go Here --

 

[Hyperfocal]

The HT improvement is only in the 10 - 15% for F@H.

Thanks for giving F@H some extra firepower.

 

[Wolfsraider]

Originally posted by: Hyperfocal
The HT improvement is only in the 10 - 15% for F@H.

Thanks for giving F@H some extra firepower.

Hyperfocal, Is that with the flags in use as well?

-forceasm = if the client or computer crash, the client thinks it is it's fault and when restarted does not use optimized code which takes like ten times longer to finish WU. This flag prevents the client from checking prior termination so that it will always use optimized fast code.

-advmethods = says that you accept the risks of doing late beta WUs, You need to use this flag to get the double point BigWUs.

Or straight install?
Just curious.

Mike

 

[BlackMountainCow]

I'd like to know that as well! I jjust set the -forceasm flag but I'm not sure about the -advmethods one.

 

[salvorhardin]

with the -advmethods flag you get large WU that take use more resources but gives you more points. for example i have received 320pt WUs that take 30 hours on a AXP3200+ and uses about 160MB of memory.

 

[GLeeM]

Originally posted by: Hyperfocal
The HT improvement is only in the 10 - 15% for F@H.

Eleven percent is the least gain I have gotten (two Gromacs)

With a Tinker and a Gromac the best I got was 31% (P4 3.0C @ 3.3)

With four BigWUs on a dual Xeon 1.6 @ 2.5 (w/1GB ram) I currently get 45% more points per day than if I only ran two!
The slower the Ghz the better the return with HT.

The BigWUs are harder to get right now. If there are enough (>100) on the server when you try you will get one.

 

[BlackMountainCow]

Good to know GLeem! So I'll definitly run with both those flags! :beer:

 

[GLeeM]

@BlackMountainCow
Yep, run two console versions. Make sure that during config you change the MachineID of the second one to 2. If you don't do this you will have many problems.

This quote by me: "The slower the Ghz the better the return with HT." is not stated right.

HT works because of the loooong pipeline in the P4 CPUs. As the Ghz gets higher the long pipeline does not cause as much delay when there is a misprediction of the next needed code or data. The more Ghz the more points per day, but the less percent increase running two on HT.

I should try running my 1.6 @ 2.5 without OC just to see how much more percent increase I would get with HT. I would get less points, but the percent increase would go way up - I bet.

 

[MEDISIN]

Originally posted by: GLeeM

I should try running my 1.6 @ 2.5 without OC just to see how much more percent increase I would get with HT. I would get less points, but the percent increase would go way up - I bet.

Only you would think of this...but I bet your right.

<Intel to GLeeM> On behalf of Intel, It is your duty to proclaim the "HT goodness" to the world.

<GLeeM to Intel> Yessir, I will sing it's praises to the depths of the AT forums, so that all will bow down and worship.


LOL...I couldn't resist.

 

[BlackMountainCow]

Well, I'm usually a die-hard AMD fan, but I recently purchased a Intel laptop computer with a 2,8 P4 HT and I got to say, so far it has surprised me a good deal. I never really though much of the HT stuff, as it was more like a PR thing or fake to me, ' cause after all, it's still only one CPU and not a real dual CPU, but I saw what this baby would do to SETI WU output. On the other hand, for ClimatePrediction.Net it was useless. So, for some tasks, HT can be a major benefit, for some it just doesn't matter. That was my initial reason for starting this thread.

:beer:

 

[MEDISIN]

Ohhhh Christian, know you've gone and used "HT" and "Fake PR" in the same sentence. Better watch your back! :evil:

 

[BlackMountainCow]

LOL Medisin! :beer::beer:

 

[GLeeM]

lol, I don't have stock in Intel, honest

It is hard to straighten out some peoples' misconceptions about IT.

 

[Unforgiven]

Originally posted by: GLeeM
lol, I don't have stock in Intel, honest

It is hard to straighten out some peoples' misconceptions about IT.

i have stock in both intel and amd so im a poster child for being a fence sitter