Thank you for your response.<div><br></div><div>Best Regards</div><div>H.D., Kim<br><br><div class="gmail_quote">2011/5/12 Mandar Gurav <span dir="ltr"><<a href="mailto:mandarwce@gmail.com">mandarwce@gmail.com</a>></span><br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Hi hyunduk !<br>
<br>
This is not about the total number of processors.... Its about to<br>
create number of processes. You can create as many number of processes<br>
as you can. Simultaneously, only those many processes(in your case 2 X<br>
6 = 12) will be executing on the actual processors. Other will be<br>
waiting for processor quantum (This is Operating system concept.. you<br>
can refer to any Operating system book...). As you can see in your<br>
computer many processes(programs) are running simultaneously. Only few<br>
of the processes are running on the processors and others are waiting<br>
for their chance. But, you cannot realize this phenomenon because<br>
within a second Operating system switches among different processes<br>
for tens of hundreds of times.<br>
<br>
You can run your program with 20,25,30 ... processes but only few (12<br>
in your case) will be executing...<br>
<font color="#888888"><br>
-- Mandar Gurav<br>
</font><div><div></div><div class="h5"><br>
On Thu, May 12, 2011 at 6:41 PM, hyunduk kim <<a href="mailto:fororigin@gmail.com">fororigin@gmail.com</a>> wrote:<br>
> Dear Pavan<br>
> The hostname of My linux machine is <a href="http://francium.ac.kr" target="_blank">francium.ac.kr</a>.<br>
> And I removed my machine as your comment.<br>
> I received message as like<br>
> [root@francium machine]# mpiexec -n 11<br>
> /usr/local/mpich2-1.3.2p1/examples/cpi<br>
> Process 0 of 11 is on francium<br>
> Process 2 of 11 is on francium<br>
> Process 3 of 11 is on francium<br>
> Process 4 of 11 is on francium<br>
> Process 5 of 11 is on francium<br>
> Process 7 of 11 is on francium<br>
> Process 8 of 11 is on francium<br>
> Process 9 of 11 is on francium<br>
> Process 10 of 11 is on francium<br>
> Process 6 of 11 is on francium<br>
> Process 1 of 11 is on francium<br>
> pi is approximately 3.1415926544231247, Error is 0.0000000008333316<br>
> wall clock time = 0.000453<br>
> In above command, the option " -n 11" means that some program is going to<br>
> use the 11 machine.<br>
> Then I modified my run command as below message.<br>
> [root@francium machine]# mpiexec -n 16<br>
> /usr/local/mpich2-1.3.2p1/examples/cpi<br>
> Process 0 of 16 is on francium<br>
> Process 1 of 16 is on francium<br>
> Process 2 of 16 is on francium<br>
> Process 3 of 16 is on francium<br>
> Process 4 of 16 is on francium<br>
> Process 6 of 16 is on francium<br>
> Process 7 of 16 is on francium<br>
> Process 8 of 16 is on francium<br>
> Process 9 of 16 is on francium<br>
> Process 12 of 16 is on francium<br>
> Process 14 of 16 is on francium<br>
> Process 10 of 16 is on francium<br>
> Process 15 of 16 is on francium<br>
> Process 11 of 16 is on francium<br>
> Process 13 of 16 is on francium<br>
> Process 5 of 16 is on francium<br>
> pi is approximately 3.1415926544231274, Error is 0.0000000008333343<br>
> wall clock time = 0.000500<br>
> In this command, I expected the error message because my linux machine is<br>
> composed of 2 CPU, and each CPU has the 6 core.(Then my machine for mpich2<br>
> is just 12.)<br>
> Question is the meaning of the option "-n" in execute command.<br>
> Thank for your kindness<br>
><br>
> H.D., Kim<br>
><br>
><br>
><br>
><br>
><br>
> 2011/5/12 Pavan Balaji <<a href="mailto:balaji@mcs.anl.gov">balaji@mcs.anl.gov</a>><br>
>><br>
>> Is there an actual machine with the name "host1" or "host2" in your setup?<br>
>><br>
>> If you are just running it on the local node, you should not give the<br>
>> -machinefile or -f option.<br>
>><br>
>> -- Pavan<br>
>><br>
>> On 05/12/2011 03:28 AM, hyunduk kim wrote:<br>
>>><br>
>>> Thanks for your response<br>
>>> However, my setup is not working.<br>
>>><br>
>>> In my check progress.<br>
>>> 1) I installed mpich2 on intel muti-core 2 cpu machine<br>
>>> 2) check : /etc/hosts file<br>
>>> 127.0.0.1 localhost.localdomain localhost<br>
>>> ::1 localhost6.localdomain6 localhost6<br>
>>><br>
>>> 3) made the machinefile for mpiexec :<br>
>>> /usr/local/mpich2/machine/machinefile<br>
>>><br>
>>> host1:6<br>
>>> host2:6<br>
>>><br>
>>> 4) run : [root@francium machine]# mpiexec -n 10 -machinefile<br>
>>> ./machinefile /usr/local/mpich2-1.3.2p1/examples/cpi<br>
>>> ==> I received messages as below<br>
>>> ssh: connect to host host1 port 22: Connection timed out<br>
>>> ssh: connect to host host2 port 22: Connection timed out<br>
>>><br>
>>> Question is :<br>
>>> 1) why do I setup passwordless login among the two hosts?<br>
>>> 2) Mpich2 was installed on the just multi-core 2 cpu machine. Why dose<br>
>>> the mpiexec try to connect host1 and host2 using port 22 ?<br>
>>> 3) Is there other method for defining the machinefile on the multi-core<br>
>>> 2 cpu machine ?<br>
>>><br>
>>> I will attach my log files.<br>
>>><br>
>>><br>
>>><br>
>>><br>
>>> _______________________________________________<br>
>>> mpich-discuss mailing list<br>
>>> <a href="mailto:mpich-discuss@mcs.anl.gov">mpich-discuss@mcs.anl.gov</a><br>
>>> <a href="https://lists.mcs.anl.gov/mailman/listinfo/mpich-discuss" target="_blank">https://lists.mcs.anl.gov/mailman/listinfo/mpich-discuss</a><br>
>><br>
>> --<br>
>> Pavan Balaji<br>
>> <a href="http://www.mcs.anl.gov/~balaji" target="_blank">http://www.mcs.anl.gov/~balaji</a><br>
><br>
><br>
<br>
<br>
<br>
</div></div>--<br>
<div><div></div><div class="h5">Mandar Gurav<br>
<a href="http://www.mandargurav.org" target="_blank">http://www.mandargurav.org</a><br>
</div></div></blockquote></div><br></div>