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<DIV dir=ltr align=left><SPAN class=673404320-22012007><FONT face=Arial
color=#0000ff size=2>If you have trouble getting MPD to run correctly, try
debugging it as described in Appendix A of the installation guide. If
it still doesn't work, send mail to <A
href="mailto:mpich2-maint@mcs.anl.gov">mpich2-maint@mcs.anl.gov</A> with
details.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=673404320-22012007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=673404320-22012007><FONT face=Arial
color=#0000ff size=2>Rajeev</FONT></SPAN></DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B> owner-mpich-discuss@mcs.anl.gov
[mailto:owner-mpich-discuss@mcs.anl.gov] <B>On Behalf Of </B>Luiz
Mendes<BR><B>Sent:</B> Monday, January 22, 2007 8:04 AM<BR><B>To:</B>
mpich-discuss<BR><B>Cc:</B> Rob Ross<BR><B>Subject:</B> Re: [MPICH] ROMIO
practice doubts<BR></FONT><BR></DIV>
<DIV></DIV>Hi all,<BR>Thanks Rob,<BR><BR>I have been reading MPI 2 book, and
other materials, and i still be in doubt with some concepts.<BR><BR>There are
some doubt topics that i havent learn yet.<BR><BR>These hints, they are
effective only in non-contiguos situations, is it right?
<BR>romio_pvfs_listio_write and read for example, they would be effective in
non contiguous situations?<BR><BR>ROMIO excuses the necessity of build
list_io_read function, when we use these above hints?<BR><BR>And talking about
Non-contiguous access, i understood it as a heterogeneous thing. For example,
in a data, we have the first 3 blocks of one type, and the next block is a
different thing with 2 blocks for example. Is it right? <BR><BR>Contiguity
refers to belong to a same element?<BR><BR>When i define an MPI_Vector for
example, i set non null strides. These blank spaces, they could be used for
other elements?<BR><BR>I am trying to make a simple benchmark to measure
bandwith, but i didnt get it works yet. <BR><BR>Non contiguouos datatypes are
only these ones that have strides? if i make a datatype that consists of a
"entire line row" in each block, it could be considered a non contiguos thing?
The hints would do any influency over it? <BR><BR>In MPICH2, i create a
mpd.hosts file, but i am not getting it works, mpdtrace doesnt tell anything
about the slave node. What should i do?<BR><BR>Thanks in advance,
luiz.<BR><BR><BR><BR><BR><BR>
<DIV><SPAN class=gmail_quote>2007/1/22, Rob Ross <<A
href="mailto:rross@mcs.anl.gov">rross@mcs.anl.gov</A>>:</SPAN>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Hi
Luiz,<BR><BR>That's exactly where the hints go. You can also use
the<BR>MPI_File_set_info() call if you like, and you can pass hints it
at<BR>MPI_File_set_view() time as
well.<BR><BR>Regards,<BR><BR>Rob<BR><BR>Luiz Mendes wrote: <BR>> Hi
all,<BR>><BR>> I have read MPI 2 book, ROMIO guide and some articles
about<BR>> optimizations for MPI IO. But i didnt see yet or i didnt
understand<BR>> where hints would be placed on MPI_File_open code.
<BR>><BR>> Should i use ROMIO hints replaceing MPI_INFO_NULL constant
in<BR>> MPI_File_open function?<BR>><BR>> Thanks in advance<BR>>
Luiz
Mendes<BR>><BR>><BR></BLOCKQUOTE></DIV><BR></BLOCKQUOTE></BODY></HTML>