Quote:JenniferCarter Oct 9th 11:13 pmVladimir,
I suggest you try running same problem on 8 threads, 16 threads and 32 threads on Kogence and see how computational time is scaling. I am guessing may be able to see that performance improves linearly initially and sub-linearly later.
As Sean said, most computational algorithms do not scale linearly. Scaling is also problem dependent.
You also have to understand what is taking time. If you try to run a very small problem on a 128 core computer, you dont expect to see much benefit because overhead is more expense and your problem is small enough to not compensate for overhead.
I apologize for the fact that I did not quite accurately formulate my question.
I would like to draw attention to the fact that only Multireference CC iterations not scaling linearly.
I want to ask you what settings I should choose for the MRCC method to achieve the highest performance on 64-128 cores
http://nwchemgit.github.io/index.php/Release66:TCE#State-Specific_Multireference_Coupled_Clu...
P.S. to Jennifer
NWCHEM has many methods of calculating and many parameters to adjust their performance. Possible default settings do not fit.
can You describe in more detail the topology of your computer and in particular the network through which the data is exchanged between processors and with which keys NWCHEM was compiled in accordance with this.
Best, Vladimir.
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