Thanks for pointing out that link. The graph makes the point I was going to
mention, i.e. that you notice a big difference in using up to about 4
processors for typical jobs, but after that point the non-parallelisable parts
of the code start to dominate and there's less improvement. This is
Le Tue, 8 Nov 2011 16:25:22 -0800,
Nat Echols nathaniel.ech...@gmail.com a écrit :
On Tue, Nov 8, 2011 at 4:22 PM, Francois Berenger beren...@riken.jp
wrote:
In the past I have been quite badly surprised by
the no-acceleration I gained when using OpenMP
with some of my programs... :(
You
On 11/09/2011 07:21 PM, Pascal wrote:
Le Tue, 8 Nov 2011 16:25:22 -0800,
Nat Echolsnathaniel.ech...@gmail.com a écrit :
On Tue, Nov 8, 2011 at 4:22 PM, Francois Berengerberen...@riken.jp
wrote:
In the past I have been quite badly surprised by
the no-acceleration I gained when using OpenMP
--
Prof. George M. Sheldrick FRS
Dept. Structural Chemistry,
University of Goettingen,
Tammannstr. 4,
D37077 Goettingen, Germany
Tel. +49-551-39-3021 or -3068
Fax. +49-551-39-22582
---BeginMessage---
In my experience, writing efficient multithreaded code is much harder
than writing efficient
Hi Ed,
in the CCP4 distribution, openmp is not enabled by default, and there
seems to be no easy way to enable it (i.e. by setting a flag at the
configure stage).
On the other hand, you can easily create a separate build for phaser
that is openmp enabled and use phaser from there. To do this,
On Tue, Nov 8, 2011 at 4:22 PM, Francois Berenger beren...@riken.jp wrote:
In the past I have been quite badly surprised by
the no-acceleration I gained when using OpenMP
with some of my programs... :(
Amdahl's law is cruel:
http://en.wikipedia.org/wiki/Amdahl's_law
This is the same reason
See page 3 of this
http://www-structmed.cimr.cam.ac.uk/phaser/ccp4-sw2011.pdf
On Wed, 2011-11-09 at 09:22 +0900, Francois Berenger wrote:
Hello,
How faster is the OpenMP version of Phaser
versus number of cores used?
In the past I have been quite badly surprised by
the no-acceleration
