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From: zimoun <zimon.toutoune@gmail.com>
To: help-guix <help-guix@gnu.org>
Subject: R, openBlas and max thread?
Date: Mon, 18 Feb 2019 16:12:41 +0100	[thread overview]
Message-ID: <CAJ3okZ1RvZDT8h6wcmLdW2BPkQiDbFgQ7JOkC02Ejst8N19g2Q@mail.gmail.com> (raw)

Dear,

I am not sure to understand if it is expected or not.

Let install R, guix package -i r, and then run the small script:

> N <- 9000;A <- array(0.1, dim=c(N,N));B <- array(0.1, dim=c(N,N))
> dim(B %*% A)

Monitoring with htop, only 8 of my 16 cores are used. Why ?
And if I have more, then again only 8 cores will be used.

Is it from OpenBlas?
I miss the compilation option forcing this behaviour. I expect that R
will use as many core as available. Right?


Thank you for any insight.

All the best,
simon

             reply	other threads:[~2019-02-18 15:13 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-02-18 15:12 zimoun [this message]
2019-02-20  4:18 ` R, openBlas and max thread? Eric Bavier
2019-02-22 15:11   ` zimoun

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