stephenbrooks.orgForumMuon1Q&Aprocessor limit?
Username: Password:
Search site:
Subscribe to thread via RSS
UnderTitan
2008-04-13 23:26:19
How many cores are supported with the current client?

If installed on a machine with 2 quad core processors, would it run on all 8 cores?  How about 4 quad core processors?

Thanks for your input.

Dan
yoyo
2008-04-14 06:27:39
Hello,
in the config file is an option:
Threads (number or 'auto'):
Therefore I would expect that if set to auto all processors and cores are used.  But I did not test it.
yoyo
Stephen Brooks
2008-04-14 11:08:23
I've not so far tried the current version with more than 4 cores.  As more cores are added the efficiency seen in the CPU usage decreases a bit: I get 95% average on 4 cores, something like 98% on two and of course 100% on one (this used to be even more pronounced before the current version).

So I'd expect you'd get 90% efficiency on 8 cores, though dual-sockets will require some inter-socket traffic, so it could be less good.  In any case, it's programmed to accept N cores, it's just that for a very large number the parallelised part of the calculation becomes proportionately smaller.

You may want to run another project to mop up the remaining 10% of cycles somehow.  To get 100% in Muon1 you'll have to run 8 single-threaded installs in different directories at the same time!
UnderTitan
2008-04-14 20:44:34
Okay.  Great!  I'll just set to run 8 different single threads.  Thanks for the input yoyo and Stephen.
Stephen Brooks
2008-04-16 12:54:46
I'd be interested to see a screenshot of the task manager CPU usage graph when you run 1 client on 8 processors (threads=auto), though.

The single client parallel mode is interesting because it actually produces each individual result quicker instead of doing 8 at once, so there's some theoretical advantages that the genetic algorithm can learn more quickly that way.  But for throughput nothing will ever beat one separate single-threaded client per core.

Another thing you might want to try is running just 2 instances with threads=auto, to see if the 2nd one uses up the remaining CPU cycles left unused by inefficiencies of the parallel algorithm of the first.
[TN]opyrt
2008-05-10 17:31:54
Hello Stephen.

I just came across these postings and thought I'd comment (seeing that you request a screenshot).  A few weeks ago I ran the client on a dual cpu quad core system.  It detected 8 cores correctly with the setting to auto, and I think it utilized approx.  97-98% CPU.  That server has since then moved to our production environment, but I've got another one incoming.  If I remember, I'll get you some screenshots.

-Kai
Stephen Brooks
2008-05-12 10:58:22
98% of 8 cores!  That must have increased your electric bill a bit.  If you have it sitting around for a few days and are using Muon1 as a soak test, you could even run the benchmark on it (see benchmarking with Mpts thread in the muon general forum).  That machine would probably beat the top score currently held by an overclocked quad core.

It would also show up any problems; I tried Muon1 on an 8-socket system but its performance was killed by synchronisation traffic, CPUs registered 100% usage but performance only scaled by about 4.5x on a 16-way system.
runesk
2008-05-16 18:27:00
I started a dual quad core this afternoon, and I took a screenshot of the task manager after about 5 minutes running.

I'll have it running this weekend, and can provide another shot monday morning.

.R
[TN]opyrt
2008-05-21 11:41:45
Are you sure you have enough RAM there, runesk? 
: contact : - - -
E-mail: sbstrudel characterstephenbrooks.org
Yahoo: scrutney_mallard
Jabber: stephenbrooksstrudel characterjabber.org
Twitter: stephenjbrooks

Site has had 16232566 accesses.