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Old 2021-09-02, 15:51   #507
VBCurtis
 
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"Curtis"
Feb 2005
Riverside, CA

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Quote:
Originally Posted by charybdis View Post
The best solution is to make CADO oversieve a bit to reduce the matrix size; you can do this by adding tasks.filter.required_excess = 0.05 to the params file (experiment with different values to see what's best for your system).
I use 0.05 for C140-C160 to reduce matrix time when running all jobs on a single machine; I think EdH (who sieves on a "farm" of a dozen or more smaller machines) uses 0.08 or 0.10. The number is a percentage of total relations, so 0.05 asks CADO to make sure there are 5% more relations than strictly necessary for filtering; this "extra" yields a usefully smaller matrix. There are diminishing returns- do not expect a setting of 0.20 to make a 30-minute matrix!

A setting of 0.04 or 0.05 also reliably (?) produces enough relations for msieve filtering to work, useful if you're using that combination of CADO sievers and msieve postprocessing.
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