FAH SMP Affinity Changer

[slugbug]

I've been reading up on this little add on which works with the Windows SMP client to optimize your folding speed.

Utility works like a Windows® service, and it is completely automatic. Once per 10 minutes Affinity Changer checks to see which cores are assigned FAH SMP processes, and if needed, reassigns them evenly, 2 processes for double-core cpu, and 1 process for each core for Quad (4-core processor).

For Affinity Changer you will need to have Microsoft .NET 2.0 framework installed.

After some time interval (10 mins) utility checks, if there are 4 processes of FahCore_a1 (one FAH SMP client). If so, and system has 2 CPUs or 2 cores, then utility assigns two processes for each core in some magic way: first core gets process with maximal memory usage, and process with minimal memory usage. Other two processes are assigned to second core.

For quad core processors, first SMP client is assigned to 1st and 3rd core, 2nd SMP client assigned to 2nd and 4th core. Assigning affinities on QUAD if you run one SMP client does not make sense.

Attention: Version 1.0.4 has 64-bit cpu support and starts automatically after install.


Link to story with download links: http://distributed.org.ua/forum/index.php?showtopic=1149

Apparently with a quad core processor I should be running two instances of the SMP client. I'll install another one and see how it goes.

edit: I've discovered that running two Windows SMP clients can be problematic. If you stop one client, you run the risk of losing the other clients work unit. Until a better Windows SMP client is available I recommend sticking with a single instance.

[werty316]

Also there are only certain instances where the SMP Affinity will be beneficial like running a quadcore wth two SMP clients but not so much on a dualcore running one SMP client. None the less using the SMP Affinity changer can give a nice PPD boost for those running a quadcore.

[Goliath182]

Cool ill get this running on my dual dual core. Give you guys some more cores to work with.

[slugbug]

Check this out:

http://img392.imageshack.us/img392/4967/fahmonfa3.jpg

Two instances of the Windows SMP client running on my Q6600@3.0ghz with the Affinity Changer installed.
I was getting about 2180ppd with a single instance running.

The first instance is ver 5.92 and the 2nd is ver 5.91. I haven't tried upgrading the 2nd to version 5.92 yet because I'm not sure if the new DeinoMPI will work with two instances running at the same time.

[bobletman]

oh cool I cant wait to start running this.

[slugbug]

I asked on the F@H forum whether you could run two v5.92 clients simultaneously and got this reply:

The v5.92 client behaves in the same was as the v5.91 client when running 2 copies on one computer. The biggest problem with either is that exiting one client may cause the 2nd client to lose it's work unit.

Now that would suck depending how far you were into the 2nd one.

[bobletman]

OK since I have a quad I wanna run to instances of the client. Well Im running Windows 2000/XP/Vista Graphical client version 5.03. And it only lets me run one instance of it. any advice would be appreciated or maybe do I just have to download a client that supports using quad cores.

[slugbug]

You'll see a big improvement with even a single SMP client. Each WU is typically worth 1760 points.

[bobletman]

You'll see a big improvement with even a single SMP client. Each WU is typically worth 1760 points.

so your saying I should just stick with the one I have?

[werty316]

so your saying I should just stick with the one I have?
No, take advantage of your quadcore by using the SMP client instead of the GUI(graphical) F@H client.

Go here: http://folding.stanford.edu/English/DownloadWinOther and download one of the SMP clients.

EDIT: this should help those as to whether or not you'll benefit from using the SMP Affinity Changer:

Quad core/four cores running 1 SMP client - there is no need to use the SMP Affinity Changer.
Quad core/four cores running 2 SMP clients - use the SMP Affinity Changer.
Duad core/two cores running 1 SMP client - there is no need to use the SMP Affinity Changer.

[bobletman]

No, take advantage of your quadcore by using the SMP client instead of the GUI(graphical) F@H client.

Go here: http://folding.stanford.edu/English/DownloadWinOther and download one of the SMP clients.

EDIT: this should help those as to whether or not you'll benefit from using the SMP Affinity Changer:

Quad core/four cores running 1 SMP client - there is no need to use the SMP Affinity Changer.
Quad core/four cores running 2 SMP clients - use the SMP Affinity Changer.
Duad core/two cores running 1 SMP client - there is no need to use the SMP Affinity Changer.


hmm right now im using 1 client that is using all 4 cores. Is there a benifit if i use 2 clients instead.

[slugbug]

Stick with one SMP client with Windows. I tried upgrading the second SMP client I installed earlier to v5.92 and it completely screwed it up, losing the work unit in the process.

Right now the only safe way to run two SMP clients is with Linux.

[ZhengHe]

Nice find slugbug. I'm not sure how useful it will be with my Dual Core, but worth trying out just in case there is even miniscule improvement, at least for a few working units. What sort of improvement have you guys had with your quad cores?

[coxmaster]

Im using the Affinity Changer on my Dual Core.. and there is a noticable difference. My average time per step has gone down about 2-3 minutes from before..

[ZhengHe]

Im using the Affinity Changer on my Dual Core.. and there is a noticable difference. My average time per step has gone down about 2-3 minutes from before..

I have seen the seen the same change with my Dual core, which has signficantly raised the average ppd. It seems that it is an application, which is useful for both quad and dual core processors as well.

[werty316]

True but its much more useful on a a quadcore.

[slugbug]

Anyone else who's using the SMP client notice that some of the smaller or odd sized work units process slower?
With a standard 1760 point WU I was getting about 2000-2100 ppd. Here's what I'm getting right now:

1440 point WU: 1504 ppd
1753 point WU: 1644 ppd
2359 point WU: 1605 ppd

[ZhengHe]

True but its much more useful on a a quadcore.

Indeed, but an additional 280 ppd is nothing to sniff at, assuming Fahmon is even remotely accurate in it recording of my WU production.

[slugbug]

I gave up trying to run two SMP clients with my quad core. I thought I'd have better luck running one v5.91 and one v5.92 since they both use a different MPI. I stopped one and immediately lost both work units :explode: