Changes between Version 10 and Version 12 of Ticket #26118


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Timestamp:
08/24/18 15:19:37 (4 years ago)
Author:
saraedum
Comment:

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  • Ticket #26118

    • Property Authors changed from to Julian Rüth
  • Ticket #26118 – Description

    v10 v12  
    88
    99The FAQ explains what these options do: https://github.com/xianyi/OpenBLAS/wiki/faq
     10
     11----
     12
     13Here are some benchmarks:
     14
     15{{{
     16sage: m=load('/tmp/matrix') # a 500x500 RDF matrix
     17sage: %timeit m.eigenvalues()
     181 loop, best of 3: 1.78 s per loop # currently
     191 loop, best of 3: 911 ms per loop # with OPENBLAS_NUM_THREADS=1
     20}}}
     21
     22Note that the first one causes 100% load on 130 of the 160 cores and the second one only causes 100% load on a single core. (Yes, it's faster anyway.)
     23
     24I also tried with all sorts of combinations of SAGE_NUM_THREADS*, OPENBLAS_MAIN_FREE and always got around 1.8s and 100% load on 130 cores. I'v sometimes seen segfaults that were not reproducible but never with OPENBLAS_NUM_THREADS=1.