Whats with AP

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Max Garth

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Message 1106082 - Posted: 14 May 2011, 10:48:29 UTC

Ever since I started TThrottling there have been increases in AP calc times. Today one has gone up to 309 hours which is a bit ridiculous.
Another point is that looking at the standard operation of my computer, the CPU temp, all cores, on normal things sits at 35 degrees C but with Boinc and 4 cores operating it sits at 65 degrees and on throttle it sits at the 60 degrees I've selected.
I find that calc times increase as soon as Throttle gets involved.
These things never bother me until I decided to look at Throttle, and now I wish the thing never existed.VBG
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Message 1106090 - Posted: 14 May 2011, 11:10:37 UTC - in response to Message 1106082.  

Well, the point of throttling the CPU is to cut down the rate/amount of usage to reach the temperature you want. So of course the WUs will take longer. What did you expect?

I had a similar problem with a 4-core machine I was running on - I noticed that though I had 3 cores (75% usage specified), it was bouncing all around. And the elapsed time clocks on the task tab was running much slower (by a factor of 2, roughly) than wall clock time. I finally figured out that I had also specified "use at most 50% of CPU time" in BOINC local prefs. When I changed that to 100% all was well, and the elapsed time ran same as wall clock time, as expected.
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Message 1106421 - Posted: 15 May 2011, 9:59:34 UTC - in response to Message 1106082.  

It is to be expected if you 'throttle' a CPU - you are, after all, effectively forcing the CPU to idle for n% of the time, often to reduce temperatures. I've no idea what CPU cooler you are using, but the temps you mention don't seem too bad to me, bearing in mind that your CPU is much 'beefier' than my humble Intel Core 2 Duo E6550. This one typically runs at 43C on 97% load (set in prefs, as I also use the PC for work related things and like to listen to music at the same time) and is still at that temp after 12 hours or more - although as the ambient temperature rises due to the warm weather, it may rise to about 46C. So, all things considered yours is looking OK, but then I don't know a great deal about your CPU specs. We all like cool CPUs though, so a better cooler might also be something to consider. I use a Scythe Ninja 2 and Arctic Silver compound.

If you want to get those 'crunching' times down, you might want to install an Optimized Application for AP and MB work units. You'll find the appropriate information in this forum, under Optimized Applications and Binaries...I think the one you'll need is the Lunatics 0.37 installer which will install the AP and MB apps for you. You may find an increase in CPU temp, but if you were to 'throttle at say, 95% CPU load (as an example) you could find your temps as they were (without TThrottle), but with a much faster rate of work. A better cooler will obviously reduce that temp, which would give you the option of using 100% CPU power. To give you some idea of what the apps can do, I usually get through an AP unit in 12 - 13 hours, and a normal MB unit is done in around 2 hours or so ('shorties' take about 30 mins) which is fairly respectable for a relatively modest CPU.



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Message 1106451 - Posted: 15 May 2011, 13:16:07 UTC
Last modified: 15 May 2011, 13:16:51 UTC

In my honest opinion it would be better to optimize the cooling instead of throttling.
Thats wasted energy.

There is always a reason why a CPU gets too hot.
Boxed coolers are very bad in generell.
Specially if you run your computer with full load most of the time.

You can buy very good coolers for only a few Bucks.
I´m using a Skythe Rasetsu for example.
It cools my 1090T @3.6 GHZ down to 50 - 52°C under full load.
Only costs ~$50.


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Message boards : Number crunching : Whats with AP


 
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