[Pw_forum] Use of pool
hqzhou at nju.edu.cn
Mon Mar 2 12:05:06 CET 2009
Of course, my tests were made on 8 CPU cores.
@Nanjing University, China
----- Original Message -----
From: "Liping Yu" <lyu7 at ncsu.edu>
To: "PWSCF Forum" <pw_forum at pwscf.org>
Sent: Tuesday, February 24, 2009 9:49 PM
Subject: Re: [Pw_forum] Use of pool
> Dear Huiqun,
> If your results are based on the same number of processes for different
> npools, they make sense to me. To my understanding, the almost linear
> time scaling of using npool means that the computer time is almost
> linear to npool (and also the total number of procs) only when we fix
> the number of the processors at each pool.
> Please correct me if I am wrong. Thanks!
> Liping Yu
> Department of Physics
> NC State University, USA
> Huiqun Zhou wrote:
>> Dear list users:
>> I happened to test duration times of calculating the system I'm
>> investigating against number of pools used. There are totally
>> 36 k points. But the results surprised me quite a lot.
>> no pool: 6m21.02s CPU time, 6m45.88s wall time
>> 2 pools: 7m19.39s CPU time, 7m38.99s wall time
>> 4 pools: 11m59.09s CPU time, 12m14.66s wall time
>> 8 pools: 21m28.77s CPU time, 21m38.71s wall time
>> The machine I'm using is an AMD box with 2 quad core shanghai.
>> Is my understanding of usage of pool wrong?
>> Huiqun Zhou
>> @Nanjing University, China
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
> Pw_forum mailing list
> Pw_forum at pwscf.org
More information about the users