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Dear Sophocles,
I was curious and I just tested Ox on a machine with 64 virtual
processors ( Amazone EC2 instance m4.16xlarge ) and threads are
correctly allocated to all cores.(on node 0 : 31CPUs are used and
on node1 : 31CPUs, they are fully working) - please see the
attached image. However I already experienced the kind of
behaviour your mention, it was due to the fact that I had some
loops that took much more time than others loops, in this case
since loops are pre-allocated to each CPU before the
parallel-forloop, it is possible that some CPUs finish their jobs
well before other CPUs . (it is typically the case if you are
estimating several models in a parallel-forloop, where models are
more complex at each iteration). So it is preferable to ensure
that each step inside the loop has a similar amount of work to
accomplish. I run the code from oxmetrics, (do not use the -rp
switch - default number of core is selected) and note that I run
the code on a single instance of an aws server. I'm not
experienced with multiple instances but a possible problem in this
case is that Ox may fail to identify all CPUs.
The following code takes 26 sec on this machine.
main()
{
decl timer = time();
decl T = 1e8;
println(T);
decl t = 0 ;
parallel for (t = 0 ; t < T; t++)
{
decl x = rann(10,10);
decl x2 = invert(x);
}
println("elapsed time: ", timespan(timer));
}
output :
Ox Professional version 7.00 (Windows_64/U/MT) (C) J.A. Doornik,
1994-2013
1e+008
elapsed time: 26.13
[log in to unmask]" type="cite">Dear All, I have tried to run Ox on an amazon cloud Windows 2012 R2 server with 64 CPUs, and I noticed that Ox does not use more than the first 32 CPUs. This is true even if I use the -rp64 switch, or when I run multiple ox programs. The number of threads increase as expected, but they are not allocated to any more than the first 32 cores. I have had the same problem on multiple instances of aws EC2 servers. Every time I cannot get Ox to use any more than the first 32 cores. Has anybody managed to use more than 32 CPUs in a windows server? Thanks for your help, Sophocles ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ https://sites.google.com/site/sophoclesmavroeidis/
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