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<DIV dir=ltr align=left><SPAN class=890550819-30112008><FONT face=Arial
color=#0000ff size=2>By the OS.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=890550819-30112008></SPAN> </DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B> mpich-discuss-bounces@mcs.anl.gov
[mailto:mpich-discuss-bounces@mcs.anl.gov] <B>On Behalf Of </B>Waruna
Ranasinghe<BR><B>Sent:</B> Sunday, November 30, 2008 10:51 AM<BR><B>To:</B>
mpich-discuss@mcs.anl.gov<BR><B>Subject:</B> Re: [mpich-discuss] Clarification
needed on runningprocessesonMPICH2<BR></FONT><BR></DIV>
<DIV></DIV>Hi, Rajeev<BR>
<DIV style="MARGIN-LEFT: 40px">Is process scheduling within a single core done
by Operating system or by MPICH itself?<BR><BR
clear=all></DIV>Regards,<BR>Waruna Ranasinghe<BR><BR><BR><BR>
<DIV class=gmail_quote>2008/11/30 Rajeev Thakur <SPAN dir=ltr><<A
href="mailto:thakur@mcs.anl.gov">thakur@mcs.anl.gov</A>></SPAN><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
<DIV>
<DIV dir=ltr align=left><SPAN><FONT face=Arial color=#0000ff size=2>Then you
can expect a slowdown if you run 6 processes on 4
cores.</FONT></SPAN></DIV><BR>
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style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: rgb(0,0,255) 2px solid; MARGIN-RIGHT: 0px">
<DIV lang=en-us dir=ltr align=left>
<HR>
<FONT face=Tahoma size=2>
<DIV class=Ih2E3d><B>From:</B> <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A> [mailto:<A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>] <B>On Behalf Of
</B>Waruna Ranasinghe<BR></DIV><B>Sent:</B> Saturday, November 29, 2008
11:32 PM
<DIV>
<DIV></DIV>
<DIV class=Wj3C7c><BR><B>To:</B> <A
href="mailto:mpich-discuss@mcs.anl.gov"
target=_blank>mpich-discuss@mcs.anl.gov</A><BR><B>Subject:</B> Re:
[mpich-discuss] Clarification needed on
runningprocessesonMPICH2<BR></DIV></DIV></FONT><BR></DIV>
<DIV>
<DIV></DIV>
<DIV class=Wj3C7c>
<DIV></DIV>no only 4<BR><BR>
<DIV class=gmail_quote>2008/11/30 Rajeev Thakur <SPAN dir=ltr><<A
href="mailto:thakur@mcs.anl.gov"
target=_blank>thakur@mcs.anl.gov</A>></SPAN><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
<DIV>
<DIV dir=ltr align=left><SPAN><FONT face=Arial color=#0000ff size=2>But
you don't have 6 cores, do you?</FONT></SPAN></DIV><BR>
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style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: rgb(0,0,255) 2px solid; MARGIN-RIGHT: 0px">
<DIV lang=en-us dir=ltr align=left>
<HR>
<FONT face=Tahoma size=2>
<DIV><B>From:</B> <A href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A> [mailto:<A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>] <B>On Behalf Of
</B>Waruna Ranasinghe<BR></DIV><B>Sent:</B> Saturday, November 29,
2008 11:03 PM
<DIV>
<DIV></DIV>
<DIV><BR><B>To:</B> <A href="mailto:mpich-discuss@mcs.anl.gov"
target=_blank>mpich-discuss@mcs.anl.gov</A><BR><B>Subject:</B> Re:
[mpich-discuss] Clarification needed on
runningprocessesonMPICH2<BR></DIV></DIV></FONT><BR></DIV>
<DIV>
<DIV></DIV>
<DIV>
<DIV></DIV>Yes, I'm sorry if you were miss led by my wordings.<BR>I
meant running two instances.<BR><BR>
<DIV class=gmail_quote>2008/11/30 Rajeev Thakur <SPAN dir=ltr><<A
href="mailto:thakur@mcs.anl.gov"
target=_blank>thakur@mcs.anl.gov</A>></SPAN><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
<DIV>
<DIV dir=ltr align=left><SPAN><FONT face=Arial color=#0000ff
size=2>If you run two instances of mpiexec -n 3 tst, you are running
a total of 6 processes, not 2 or 3. </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN><FONT face=Arial color=#0000ff
size=2>Rajeev</FONT></SPAN></DIV><BR>
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style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: rgb(0,0,255) 2px solid; MARGIN-RIGHT: 0px">
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<HR>
<FONT face=Tahoma size=2>
<DIV><B>From:</B> <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A> [mailto:<A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>] <B>On Behalf
Of </B>Waruna Ranasinghe<BR></DIV><B>Sent:</B> Saturday, November
29, 2008 5:38 AM
<DIV>
<DIV></DIV>
<DIV><BR><B>To:</B> <A href="mailto:mpich-discuss@mcs.anl.gov"
target=_blank>mpich-discuss@mcs.anl.gov</A><BR><B>Subject:</B> Re:
[mpich-discuss] Clarification needed on
runningprocessesonMPICH2<BR></DIV></DIV></FONT><BR></DIV>
<DIV>
<DIV></DIV>
<DIV>
<DIV></DIV>>What do you mean by "one process" when it is
clearly 3<BR>>processes are running ? When you say 2
processes of tst,<BR>>do you mean you launched two instances
of<BR>>"mpiexec -n 3 ./tst" simultaneously.<BR><BR>Yes, I meant
of launching two instances of "mpiexec -n 3 ./tst"
simultaneously.<BR><BR>I could not reach the MPICH cluster until
monday, so that I'll send the modified programme on
Monday.<BR><BR>Thank You,<BR>Waruna<BR><BR>
<DIV class=gmail_quote>2008/11/29 Anthony Chan <SPAN
dir=ltr><<A href="mailto:chan@mcs.anl.gov"
target=_blank>chan@mcs.anl.gov</A>></SPAN><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">>From
your Readme file:<BR><BR>> mpiexec -n 3
<path><BR>><BR>> output:<BR>> when only one
process runs<BR>><BR>> 0:Total: 499999999500000000 : Time:
9.272023<BR>> 2:Total: 499999999500000000 : Time:
10.722239<BR>> 1:Total: 499999999500000000 : Time:
11.324907<BR>><BR>> When two processes of 'tst' runs in
the same time<BR>><BR>> 0:Total: 499999999500000000 :
Time: 9.538206<BR>> 2:Total: 499999999500000000 : Time:
16.045104<BR>> 1:Total: 499999999500000000 : Time:
22.400754<BR><BR>What do you mean by "one process" when it is
clearly 3<BR>processes are running ? When you say 2
processes of tst,<BR>do you mean you launched two instances
of<BR>"mpiexec -n 3 ./tst" simultaneously.<BR><BR>Could you add
the following lines to your tst.cpp<BR><BR>
char host_name[ MPI_MAX_PROCESSOR_NAME
];<BR> int
namelen;<BR>
MPI_Get_processor_name( host_name, &namelen
);<BR> printf("rank %d running
on %s\n", rank, host_name);<BR><BR>before first fflush(stdout)
to show the location of each process.<BR>Rerun your experiments
and let us know the result.<BR><BR>Also, you can use MPI_Wtime()
instead of Duration.cpp that may<BR>simplify your test
program.<BR>
<DIV>
<DIV></DIV>
<DIV><BR>A.Chan<BR><BR>----- "Waruna Ranasinghe" <<A
href="mailto:warunapww@gmail.com"
target=_blank>warunapww@gmail.com</A>> wrote:<BR><BR>> Hi
Rajeev,<BR>> Here's test programme. It's just for testing.
The results I got, are<BR>> in the<BR>> read me file in
the attachment<BR>><BR>> Thank You<BR>>
Waruna<BR>><BR>> 2008/11/27 Rajeev Thakur <<A
href="mailto:thakur@mcs.anl.gov"
target=_blank>thakur@mcs.anl.gov</A>><BR>><BR>> >
In that case, what kind of program are you running? Can
you send us<BR>> a<BR>> > small test program.<BR>>
><BR>> > Rajeev<BR>> ><BR>> >
------------------------------<BR>> > *From:* <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>
[mailto:<BR>> > <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>] *On Behalf
Of *Waruna Ranasinghe<BR>> > *Sent:* Wednesday, November
26, 2008 9:05 PM<BR>> ><BR>> > *To:* <A
href="mailto:mpich-discuss@mcs.anl.gov"
target=_blank>mpich-discuss@mcs.anl.gov</A><BR>> >
*Subject:* Re: [mpich-discuss] Clarification needed on<BR>>
> runningprocessesonMPICH2<BR>> ><BR>> > Hi
Rajeev,<BR>> > There's no doubt that process runs on all 3
machines.<BR>> > I have tried cpi example and it prints
the hostnames of 3 machines<BR>> ><BR>> > mpiexec -l
-n 3 <path to process><BR>> > (the same path is
available in all 3 machines)<BR>> ><BR>> > Thank
you<BR>> > Waruna<BR>> ><BR>> ><BR>> >
2008/11/26 Rajeev Thakur <<A href="mailto:thakur@mcs.anl.gov"
target=_blank>thakur@mcs.anl.gov</A>><BR>> ><BR>>
>> Make sure the processes are actually running on
the 3 machines.<BR>> Try the<BR>> >> cpi example in
the examples directory. It prints out the hostname.<BR>> How
are<BR>> >> you running the job?<BR>>
>><BR>> >> Rajeev<BR>> >><BR>>
>> ------------------------------<BR>> >>
*From:* <A href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>
[mailto:<BR>> >> <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>] *On Behalf
Of *Waruna<BR>> Ranasinghe<BR>> >> *Sent:*
Wednesday, November 26, 2008 11:07 AM<BR>> >><BR>>
>> *To:* <A href="mailto:mpich-discuss@mcs.anl.gov"
target=_blank>mpich-discuss@mcs.anl.gov</A><BR>> >>
*Subject:* Re: [mpich-discuss] Clarification needed on
running<BR>> >> processesonMPICH2<BR>>
>><BR>> >> Fedora 8 - MPICH2 one machine
with core-2-duo - master<BR>> >> two machines with one
core<BR>> >> all together 3 nodes<BR>>
>><BR>> >> 2008/11/26 Rajeev Thakur <<A
href="mailto:thakur@mcs.anl.gov"
target=_blank>thakur@mcs.anl.gov</A>><BR>>
>><BR>> >>> What kind of environment are
you running on (how many machines,<BR>> how<BR>>
>>> many cores each)?<BR>> >>><BR>>
>>> Rajeev<BR>> >>><BR>> >>>
------------------------------<BR>> >>>
*From:* <A href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>
[mailto:<BR>> >>> <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>] *On Behalf
Of *Waruna<BR>> Ranasinghe<BR>> >>> *Sent:*
Wednesday, November 26, 2008 2:15 AM<BR>> >>> *To:*
<A href="mailto:mpich-discuss@mcs.anl.gov"
target=_blank>mpich-discuss@mcs.anl.gov</A><BR>> >>>
*Subject:* Re: [mpich-discuss] Clarification needed on
running<BR>> processes<BR>> >>> onMPICH2<BR>>
>>><BR>> >>> Hi Anthony,<BR>>
>>> I'm sorry, in this case I have to disagree with
you.<BR>> >>> Because it is not max(t1,t2) but t1+t2
(this is the real result I<BR>> got)<BR>> >>> I
use fflush(stdout) also<BR>> >>><BR>>
>>> What I think is that, Cluster runs two programmes
alternatively.<BR>> >>> i.e. Process A runs for a
while (say t3 seconds) then process B<BR>> for<BR>>
>>> sometime and so on.<BR>> >>> Therefore,
ultimately both the processes will run for t1+t2<BR>>
>>><BR>> >>> Cluster: MPICH2<BR>>
>>> Fedora 8<BR>> >>><BR>> >>>
2008/11/26 Anthony Chan <<A href="mailto:chan@mcs.anl.gov"
target=_blank>chan@mcs.anl.gov</A>><BR>>
>>><BR>> >>>><BR>> >>>>
If process A and B are launched by mpiexec, the time
taken<BR>> >>>> by mpiexec should be max(t1,t2)
not t1 + t2. As Rajeev said,<BR>> >>>> calling
fflush(stdout) after each printf() is the fastest way<BR>>
>>>> to get each process's stdout printed to your
console.<BR>> >>>><BR>> >>>>
A.Chan<BR>> >>>> ----- "Waruna Ranasinghe"
<<A href="mailto:warunapww@gmail.com"
target=_blank>warunapww@gmail.com</A>> wrote:<BR>>
>>>><BR>> >>>> > Hi
Rajeev,<BR>> >>>> > Actually this is not what
I'm talking about.<BR>> >>>> > Say there are
processes A and B<BR>> >>>> > Process A
utilize 100% of the cpu while it runs. The answer<BR>>
will<BR>> >>>> > appear in<BR>>
>>>> > t1 seconds<BR>> >>>> >
Process B also utilize 100% of the cpu while it runs.
The<BR>> answer will<BR>> >>>> >
appear<BR>> >>>> > in t2 seconds<BR>>
>>>> ><BR>> >>>> > When I run
both the process A and B at the same time, The both<BR>>
answers<BR>> >>>> > will<BR>>
>>>> > appear in t1 + t2 seconds. where as I want
to get the Process<BR>> A's<BR>> >>>> >
answer<BR>> >>>> > first. (Here Process A is
submitted before Process B)<BR>> >>>>
><BR>> >>>> > Is there anything that I can
do to make this happen.<BR>> >>>> ><BR>>
>>>> > Thank You,<BR>> >>>> >
Waruna<BR>> >>>> ><BR>> >>>>
> 2008/11/26 Rajeev Thakur <<A
href="mailto:thakur@mcs.anl.gov"
target=_blank>thakur@mcs.anl.gov</A>><BR>>
>>>> ><BR>> >>>> > >
If you are refering to the output of "printf", you can
try<BR>> adding<BR>> >>>> > an<BR>>
>>>> > > fflush(stdout) after the printf. You
don't have much control<BR>> over<BR>> >>>>
> the order<BR>> >>>> > > in which it is
printed from different processes.<BR>> >>>> >
><BR>> >>>> > > Rajeev<BR>>
>>>> > ><BR>> >>>> > >
------------------------------<BR>> >>>>
> > *From:* <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>
[mailto:<BR>> >>>> > > <A
href="mailto:mpich-discuss-bounces@mcs.anl.gov"
target=_blank>mpich-discuss-bounces@mcs.anl.gov</A>] *On Behalf
Of *Waruna<BR>> Ranasinghe<BR>> >>>> > >
*Sent:* Tuesday, November 25, 2008 1:35 AM<BR>>
>>>> > > *To:* <A
href="mailto:mpich-discuss@mcs.anl.gov"
target=_blank>mpich-discuss@mcs.anl.gov</A><BR>>
>>>> > > *Subject:* [mpich-discuss]
Clarification needed on running<BR>> processes<BR>>
>>>> > on<BR>> >>>> > >
MPICH2<BR>> >>>> > ><BR>>
>>>> > > Hi all,<BR>> >>>> >
> I submitted 3 processes at the same time using mpiexec.
the<BR>> results<BR>> >>>> > of
each<BR>> >>>> > > process appears only
after all the processes have finished.<BR>> (I guess<BR>>
>>>> > that<BR>> >>>> > >
the way mpich schedule it).<BR>> >>>> > >
What if I want to get the result of the process, which
was<BR>> submitted<BR>> >>>> >
first,<BR>> >>>> > > first. (like first in
first out).<BR>> >>>> > ><BR>>
>>>> > > I use MPICH2 cluster in Fedora 8
(with mpd)<BR>> >>>> > ><BR>>
>>>> > > Thank you.<BR>> >>>>
> > Waruna Ranasinghe<BR>> >>>> >
><BR>> >>>> > ><BR>>
>>>><BR>> >>><BR>>
>>><BR>> >><BR>>
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