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Old 2009-03-03, 07:35   #3
Batalov's Avatar
Mar 2008

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Originally Posted by mdettweiler View Post
One other, somewhat unrelated bug(?) that I noticed during the final and successful attempt to run the postprocessing was that despite the fact that I ran msieve with the "-t 2" command line flag to run on both cores of my computer, it only ran single-threaded during the linear algebra stage. I'm not sure if this is a bug, or if this is somehow this was due to the earlier wonkiness due to all the extra relations.
Well, you know, the help of more than 1 thread can turn into a disservice, that's why it is not a bug, but a feature. It is built-in to do so (under a certain size). It is not related.

You know, in short, BL scaling up is very sublinear, and the less the job, the less sense -t 2 makes. So it is forced to be -t 1 in the code under a certain size. Even for large (but not very large) jobs, on a more-than-4-cpu cluster, I've learned to live and let live and not use more than -t 4. (live and let live? Just watched Bond-21... Rubbish. )
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