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Old 2010-12-11, 03:43   #11
Mini-Geek
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"Tim Sorbera"
Aug 2006
San Antonio, TX USA

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Quote:
Originally Posted by mdettweiler View Post
Note that you can also set MaxHighMemWorkers=1 in prime.txt to ensure that only one worker runs stage 2 at any given time. (If two workers need to run stage 2, the second one will put its stage 2 on hold and move on to stage 1 of the next assignment until the first worker's stage 2 finishes.) With this, you can "safely" run all four cores on P-1.
MaxHighMemWorkers=2 would be better, because otherwise you'd always have 3 cores running stage 1 and 1 core running stage 2. Since they take roughly (in a test of CPU credit just now, the whole thing should take about 2.076 times longer than stage 1, so that's a pretty close "roughly") the same time, stage 2 would continually fall behind stage 1. Obviously, that is not a good situation.
Note that "Default [setting for MaxHighMemWorkers] is available memory / 200MB."
Also remember that Memory can be worker-specific: (particularly useful for a situation where you want each worker to use up to, say, 250 MB, regardless of what the other workers are doing; this didn't work correctly in the past, but newer versions have it fixed)
Code:
The Memory=n setting in local.txt refers to the total amount of memory the
program can use.  You can also put this in the [Worker #n] section to place
a maximum amount of memory that one particular worker can use.

Last fiddled with by Mini-Geek on 2010-12-11 at 03:54
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