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From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2007-10-24 15:43:51


This is quite likely because of a "feature" in how the OMPI v1.2
series handles its plugins. In OMPI <=v1.2.x, Open MPI opens all
plugins that it can find and *then* applies the filter that you
provide (e.g., via the "btl" MCA param) to close / ignore certain
plugins.

In OMPI >=v1.3, we [effectively] apply the filter *before* opening
plugins. So "--mca btl ^openib" will actually prevent the openib BTL
plugin from being loaded.

I'm guessing that what you're seeing today is because we're opening
the openib BTL on a system where the OpenFabrics support libraries
are not available, and therefore the dlopen() fails. The error
string that we get back from libltdl is the somewhat-misleading "file
not found (ignored)", and that's what we print (note that ltdl is
referring to the fact that a dependent library is not found).

On Oct 24, 2007, at 9:51 AM, Dirk Eddelbuettel wrote:

>
> I've been scratching my head over this:
>
> lnx01:/usr/lib> orterun -n 2 --mca btl ^openib ~/c++/tests/mpitest
> [lnx01:14417] mca: base: component_find: unable to open btl openib:
> file not found (ignored)
> [lnx01:14418] mca: base: component_find: unable to open btl openib:
> file not found (ignored)
> Hello world, I'm process 0
> Hello world, I'm process 1
> lnx01:/usr/lib> grep openib /etc/openmpi/openmpi-mca-params.conf
> # btl = ^openib
> btl = ^openib
> lnx01:/usr/lib> orterun -n 2 ~/c++/tests/mpitest
> [lnx01:14429] mca: base: component_find: unable to open btl openib:
> file not found (ignored)
> [lnx01:14430] mca: base: component_find: unable to open btl openib:
> file not found (ignored)
> Hello world, I'm process 0
> Hello world, I'm process 1
>
> and when I strace it, I get
>
> uname({sys="Linux", node="lnx01", ...}) = 0
> open("/etc/openmpi/openmpi-mca-params.conf", O_RDONLY) = 3
> ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbf820698) = -1 ENOTTY
> (Inappropriate ioctl for device)
> fstat64(3, {st_mode=S_IFREG|0644, st_size=2877, ...}) = 0
> mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
> -1, 0) = 0xb7f72000
> read(3, "#\n# Copyright (c) 2004-2005 The "..., 8192) = 2877
> read(3, "", 4096) = 0
> read(3, "", 8192) = 0
> ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbf8205f8) = -1 ENOTTY
> (Inappropriate ioctl for device)
> close(3) = 0
> munmap(0xb7f72000, 4096) = 0
>
> Why can't I suppress the dreaded Infinityband message?
>
> System is Ubuntu 7.04 with 'ported' (ie locally recompiled) current
> Open MPI packages
> from Debian.
>
> Dirk
>
> --
> Three out of two people have difficulties with fractions.
> _______________________________________________
> users mailing list
> users_at_[hidden]
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-- 
Jeff Squyres
Cisco Systems