Platform LSF Reference Version 6.2

Environment Variables
Platform LSF Reference
281
If the output fails or cannot be read, LSB_MAILSIZE is set to -1 and the output is
sent by email using LSB_MAILPROG if specified in
lsf.conf.
◆ Undefined
If you use the
-o or -e options of bsub, the output is redirected to an output file.
Because the output is not sent by email in this case, LSB_MAILSIZE is not used
and LSB_MAILPROG is not called.
If the
-N option is used with the -o option of bsub, LSB_MAILSIZE is not set.
Where defined
Set by sbatchd when the custom mail program specified by LSB_MAILPROG in
lsf.conf is called.
LSB_MCPU_HOSTS
Syntax LSB_MCPU_HOSTS="host_nameA num_processors1 host_nameB
num_processors2..."
Description
Contains a list of the hosts and the number of CPUs used to run a job.
Valid values
num_processors1
, num_processors2,... refer to the number of CPUs used on
host_nameA, host_nameB,..., respectively
Default
Undefined
Notes
The environment variables LSB_HOSTS and LSB_MCPU_HOSTS both contain the
same information, but the information is presented in different formats.
LSB_MCPU_HOSTS uses a shorter format than LSB_HOSTS. As a general rule,
sbatchd sets both these variables. However, for some parallel jobs, LSB_HOSTS is not
set.
For parallel jobs, several CPUs are used, and the length of LSB_HOSTS can become
very long.
sbatchd needs to spend a lot of time parsing the string. If the size of
LSB_HOSTS exceeds 4096 bytes, LSB_HOSTS is ignored, and
sbatchd sets only
LSB_MCPU_HOSTS.
To verify the hosts and CPUs used for your dispatched job, check the value of
LSB_HOSTS for single CPU jobs, and check the value of LSB_MCPU_HOSTS for
parallel jobs.
Where defined
Set by sbatchd before starting a job on the execution host
Example
When the you submit a job with the -m and -n options of bsub, for example,
% bsub -m "hostA hostB" -n 6 job
sbatchd sets the environment variables LSB_HOSTS and LSB_MCPU_HOSTS as
follows:
LSB_HOSTS= "hostA hostA hostA hostB hostB hostB"
LSB_MCPU_HOSTS="hostA 3 hostB 3"
Both variables are set in order to maintain compatibility with earlier versions.
See also
LSB_HOSTS