4
This file describes what must be done to start distributed memory MPI jobs
5
that use the faster ATM connection instead of slow ethernet connections.
11
MPI will automatically use ATM interconnections in case the MPI machinefile
12
contains ATM hostnames instead of regular hostnames. The machine file is
13
created by the startup script 'startmpi.sh' for MPI parallel environments
14
according the decisions of the Grid Engine scheduler. The mapping from
15
regular hostnames into ATM hostnames should be done by the startup script
16
for MPI parallel environments.
22
Search in the script $SGE_ROOT/mpi/startmpi.sh for a comment containing
23
the acronym ATM. The command after this comment
27
writes regular hostnames as they come from scheduler into the machinefile.
28
Ensure that the regular hostname is converted - according to your scheme of
29
name mapping - into an ATM hostname. If for example your scheme is to add
30
'ATM' to each regular hostname in order to get an ATM hostname then you
31
could perform mapping easily by replacing the line with
36
3. mpirun uses 'hostname'
37
-------------------------
39
It is possible that the mapped hostnames cause trouble in the 'mpirun'
40
script. 'mpirun' uses the 'hostname' command to retrieve the local hostname.
41
'mpirun' compares this hostname with hostnames in the machine file
42
containing ATM hostnames. The regular 'hostname' command does not return ATM
43
hostnames and thus the comparation of hostnames fails which leads to a wrong
44
distribution of tasks. A clean way to fix this problem is to use the
45
hostname wrapper in this directory. You can enforce the use of this wrapper
46
by placing it in the $TMPDIR directory which is created for each job. The
47
startup script for mpi 'startmpi.sh' will do this for you if it is started
48
using the -catch_hostname option by installing a symbolic link. Note that
49
this will not work in case
51
$SGE_ROOT/mpi/hostname
53
is not available at all execution hosts. If so feel free to use rcp, ftp in
54
order to make the 'hostname' wrapper available under $TMPDIR/hostname
60
The Contents of this file are made available subject to the terms of the Sun
61
Industry Standards Source License Version 1.2
63
Sun Microsystems Inc., March, 2001
65
Sun Industry Standards Source License Version 1.2
66
=================================================
68
The contents of this file are subject to the Sun Industry Standards Source
69
License Version 1.2 (the "License"); You may not use this file except in
70
compliance with the License. You may obtain a copy of the License at
71
http://gridengine.sunsource.net/Gridengine_SISSL_license.html
73
Software provided under this License is provided on an "AS IS" basis,
74
WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
75
WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
76
MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
78
See the License for the specific provisions governing your rights and
79
obligations concerning the Software.
81
The Initial Developer of the Original Code is: Sun Microsystems, Inc.
83
Copyright: 2001 by Sun Microsystems, Inc.