Seti@Home optimized science apps and information

Optimized Seti@Home apps => Windows => Topic started by: Raptor on 04 Apr 2007, 10:41:39 am

Title: v2.2B stuttering
Post by: Raptor on 04 Apr 2007, 10:41:39 am
I've been a loyal SETI@home user since 1999. Ever since I started buying more powerful PC's I started looking at optimized SETI clients. I've used various clients over time, but stopped at the KWSN optimized clients because of the regular updates.

My PC (C2D E6600 @ 3.33 GHz) is running 24/7, with BOINC/SETI running in the background as a service.

My question regarding the latest version of the SETI client (v2.2B): why is it that every time a workunit changes (every 50 minutes per core) I get stuttering while doing anything for 3-5 seconds? It's really annoying, and has gotten me so annoyed that I'm writing this post. Is there anything I can do to prevent the clients from causing stuttering on my PC, other than reverting to v1.3 clients?

Before you ask, my PC is 100% stable (thoroughly tested with various tests for up to 72hrs continuous running).

PS: I'm not implying that I'm demanding anything or that I'm not very thankful for the time people put into making these optimized clients.
Title: Re: v2.2B stuttering
Post by: Josef W. Segur on 04 Apr 2007, 04:02:03 pm
There's nothing you can do with 2.2B to avoid the issue. This MSDN article (http://msdn2.microsoft.com/en-us/library/ms685100.aspx) gives the breakdown of thread base priority for Windows, BOINC starts science applications at NORMAL_PRIORITY_CLASS process priority and during one of the initialization procedures the worker thread priority is lowered to THREAD_PRIORITY_IDLE, giving the worker thread a base priority of 1 (as low as possible). For the 2.2B tests of which subroutines are quickest, we boost the process priority to REALTIME_PRIORITY_CLASS.

We'll experiment with other changed settings for future releases, and hope we can find a combination which will both give good testing and not be quite as disturbing.
                                                                                    Joe
Title: Re: v2.2B stuttering
Post by: Raptor on 05 Apr 2007, 06:14:54 am
Can you give me an estimate on how much time I'd lose per WU by reverting to v1.3 (which didn't cause stuttering)? Would I be losing any work by reverting?

Is this the final path development will take with the KWSN client? (raise the priority for a couple of seconds per WU)

Would I be better off using one of the non-C2D SSSE3 optimized v2.0 clients? If so, which would you recommend: P4/PD or P-M (which AFAIK more closely resembles the inner-workings of C2D)?
Title: Re: v2.2B stuttering
Post by: Josef W. Segur on 05 Apr 2007, 10:29:54 am
...
Is this the final path development will take with the KWSN client? (raise the priority for a couple of seconds per WU)

Probably, but maybe only a small boost to priority to get above Windows' background tasks.

Quote
Would I be better off using one of the non-C2D SSSE3 optimized v2.0 clients? If so, which would you recommend: P4/PD or P-M (which AFAIK more closely resembles the inner-workings of C2D)?

No, the routines which are tested are determined by your CPU capabilities so for this issue a different version wouldn't help.
                                                                               Joe
Title: Re: v2.2B stuttering
Post by: Raptor on 10 Apr 2007, 05:32:15 pm
Okay, thanks for the info.

I've reverted to the old v1.3 "Intel Core 2 SSSE3 optimized 5.15 app" and am awaiting a newer version that doesn't cause stuttering. Any news when/if that might happen anytime soon?

<edit>
Weird thing I noticed today. Ever since I reverted to the old v1.3 app all I've been getting is 0 credit for any WU I report.
my PC link (http://setiathome.berkeley.edu/results.php?hostid=2700797)
WU link 1 (http://setiathome.berkeley.edu/workunit.php?wuid=122835129)
WU link 2 (http://setiathome.berkeley.edu/workunit.php?wuid=122835123)
(you can see more WUs by clicking on the PC link above)

All I get is "Validate state: Result was reported too late to validate", even though the report deadline hasn't passed yet.

Crunch time for a WU went up by ~23%

<later edit>
I've just switched to Ubuntu Feisty Fawn, and am running the v2.2B apps, No stuttering whatsoever. Also WUs are finished a bit faster.