[mpich-discuss] Clarification needed on running processesonMPICH2

[Waruna Ranasinghe]

Hi Rajeev,
There's no doubt that process runs on all 3 machines.
I have tried cpi example and it prints the hostnames of 3 machines

mpiexec -l -n 3 <path to process>
(the same path is available in all 3 machines)

Thank you
Waruna


2008/11/26 Rajeev Thakur <thakur at mcs.anl.gov>

>  Make sure the processes are actually running on the 3 machines. Try the
> cpi example in the examples directory. It prints out the hostname. How are
> you running the job?
>
> Rajeev
>
>  ------------------------------
> *From:* mpich-discuss-bounces at mcs.anl.gov [mailto:
> mpich-discuss-bounces at mcs.anl.gov] *On Behalf Of *Waruna Ranasinghe
> *Sent:* Wednesday, November 26, 2008 11:07 AM
>
> *To:* mpich-discuss at mcs.anl.gov
> *Subject:* Re: [mpich-discuss] Clarification needed on running
> processesonMPICH2
>
> Fedora 8 - MPICH2 one machine with core-2-duo - master
> two machines with one core
> all together 3 nodes
>
> 2008/11/26 Rajeev Thakur <thakur at mcs.anl.gov>
>
>>  What kind of environment are you running on (how many machines, how many
>> cores each)?
>>
>> Rajeev
>>
>>  ------------------------------
>>  *From:* mpich-discuss-bounces at mcs.anl.gov [mailto:
>> mpich-discuss-bounces at mcs.anl.gov] *On Behalf Of *Waruna Ranasinghe
>> *Sent:* Wednesday, November 26, 2008 2:15 AM
>> *To:* mpich-discuss at mcs.anl.gov
>> *Subject:* Re: [mpich-discuss] Clarification needed on running processes
>> onMPICH2
>>
>>   Hi Anthony,
>> I'm sorry, in this case I have to disagree with you.
>> Because it is not max(t1,t2) but t1+t2 (this is the real result I got)
>> I use fflush(stdout) also
>>
>> What I think is that, Cluster runs two programmes alternatively.
>> i.e. Process A runs for a while (say t3 seconds) then process B for
>> sometime and so on.
>> Therefore, ultimately both the processes will run for t1+t2
>>
>> Cluster: MPICH2
>> Fedora 8
>>
>> 2008/11/26 Anthony Chan <chan at mcs.anl.gov>
>>
>>>
>>> If process A and B are launched by mpiexec, the time taken
>>> by mpiexec should be max(t1,t2) not t1 + t2. As Rajeev said,
>>> calling fflush(stdout) after each printf() is the fastest way
>>> to get each process's stdout printed to your console.
>>>
>>> A.Chan
>>>  ----- "Waruna Ranasinghe" <warunapww at gmail.com> wrote:
>>>
>>> > Hi Rajeev,
>>> > Actually this is not what I'm talking about.
>>> > Say there are processes A and B
>>> > Process A utilize 100% of the cpu while it runs. The answer will
>>> > appear in
>>> > t1 seconds
>>> > Process B also utilize 100% of the cpu while it runs. The answer will
>>> > appear
>>> > in t2 seconds
>>> >
>>> > When I run both the process A and B at the same time, The both answers
>>> > will
>>> > appear in t1 + t2 seconds. where as I want to get the Process A's
>>> > answer
>>> > first. (Here Process A is submitted before Process B)
>>> >
>>> > Is there anything that I can do to make this happen.
>>> >
>>> > Thank You,
>>> > Waruna
>>> >
>>> > 2008/11/26 Rajeev Thakur <thakur at mcs.anl.gov>
>>> >
>>> > >  If you are refering to the output of "printf", you can try adding
>>> > an
>>> > > fflush(stdout) after the printf. You don't have much control over
>>> > the order
>>> > > in which it is printed from different processes.
>>> > >
>>> > > Rajeev
>>> > >
>>> > >  ------------------------------
>>> > > *From:* mpich-discuss-bounces at mcs.anl.gov [mailto:
>>> > > mpich-discuss-bounces at mcs.anl.gov] *On Behalf Of *Waruna Ranasinghe
>>> > > *Sent:* Tuesday, November 25, 2008 1:35 AM
>>> > > *To:* mpich-discuss at mcs.anl.gov
>>> > > *Subject:* [mpich-discuss] Clarification needed on running processes
>>> > on
>>> > > MPICH2
>>> > >
>>> > > Hi all,
>>> > > I submitted 3 processes at the same time using mpiexec. the results
>>> > of each
>>> > > process appears only after all the processes have finished. (I guess
>>> > that
>>> > > the way mpich schedule it).
>>> > > What if I want to get the result of the process, which was submitted
>>> > first,
>>> > > first. (like first in first out).
>>> > >
>>> > > I use MPICH2 cluster in Fedora 8 (with mpd)
>>> > >
>>> > > Thank you.
>>> > > Waruna Ranasinghe
>>> > >
>>> > >
>>>
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/mpich-discuss/attachments/20081127/681ad380/attachment.htm>