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From: Gleb Natapov (glebn_at_[hidden])
Date: 2007-08-29 09:56:32


On Wed, Aug 29, 2007 at 04:48:07PM +0300, Gleb Natapov wrote:
> Is this trunk or 1.2?
Oops. I should read more carefully :) This is trunk.

>
> On Wed, Aug 29, 2007 at 09:40:30AM -0400, Terry D. Dontje wrote:
> > I have a program that does a simple bucket brigade of sends and receives
> > where rank 0 is the start and repeatedly sends to rank 1 until a certain
> > amount of time has passed and then it sends and all done packet.
> >
> > Running this under np=2 always works. However, when I run with greater
> > than 2 using only the SM btl the program usually hangs and one of the
> > processes has a long stack that has a lot of the following 3 calls in it:
> >
> > [25] opal_progress(), line 187 in "opal_progress.c"
> > [26] mca_btl_sm_component_progress(), line 397 in "btl_sm_component.c"
> > [27] mca_bml_r2_progress(), line 110 in "bml_r2.c"
> >
> > When stepping through the ompi_fifo_write_to_head routine it looks like
> > the fifo has overflowed.
> >
> > I am wondering if what is happening is rank 0 has sent a bunch of
> > messages that have exhausted the
> > resources such that one of the middle ranks which is in the process of
> > sending cannot send and therefore
> > never gets to the point of trying to receive the messages from rank 0?
> >
> > Is the above a possible scenario or are messages periodically bled off
> > the SM BTL's fifos?
> >
> > Note, I have seen np=3 pass sometimes and I can get it to pass reliably
> > if I raise the shared memory space used by the BTL. This is using the
> > trunk.
> >
> >
> > --td
> >
> >
> > _______________________________________________
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> > devel_at_[hidden]
> > http://www.open-mpi.org/mailman/listinfo.cgi/devel
>
> --
> Gleb.
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--
			Gleb.