20170919, 07:28  #1 
(loop (#_fork))
Feb 2006
Cambridge, England
1100011101110_{2} Posts 
Using 16e on smaller numbers
I've just finished sieving the log=185.44 122!+1 cofactor with 16e/32LP. 350M relations (295M unique) from sieving 30M132.4M (because I wanted a multiple of 128 jobs given my cluster) gave a 15.77M matrix at density 124; this is much easier than the 26.1M density120 matrix that nfs@home got with 365M/291M relations at 15e/32 on the only slightly harder 114!+1 cofactor.
A bit slower sieving per relation Code:
wheat@wheat:/home/nfsworld/factorial/F122p/tt$ cat 16e22.t total yield: 35827, q=134010001 (0.69377 sec/rel) wheat@wheat:/home/nfsworld/factorial/F122p/tt$ cat 15e22.t total yield: 16056, q=134009999 (0.61100 sec/rel) Last fiddled with by fivemack on 20170919 at 07:29 
20170919, 07:45  #2 
"Carlos Pinho"
Oct 2011
Milton Keynes, UK
5·7·139 Posts 
And you have more cores connected to 16e V5 since it gives more points so it will be sieved even faster.
What about memory allocated by thread? People are complaining about the higher usage of memory when you run the 15e application with the 16e one. Edit: oops, though this thread was on the NFS@Home. Last fiddled with by pinhodecarlos on 20170919 at 07:49 
20170919, 08:29  #3 
"Curtis"
Feb 2005
Riverside, CA
3^{3}×173 Posts 
Is it possible the new matrix was easier in part because you chose lower alim/rlim for your 16e run than NFS@home chose for 15e?
I've been wondering how (if?) matrix size scales with alim/rlim choice, holding LP and input difficulty fixed. Specifically, wondering if some of the jobs presently going to 14e with alim = 268M would produce smaller matrices on 15e with alim = 134M or thereabouts. 
20170919, 08:52  #4  
(loop (#_fork))
Feb 2006
Cambridge, England
2×3,191 Posts 
Quote:


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