CSAR Bulletin issued in April 2003

Withdrawal of NQE from fermat

Although LSF has been the default batch system on fermat for a number of months, a number of CPUs were retained temporarily for NQE, mainly for single-cpu jobs.

The bsingle command will now allow single-cpu jobs under LSF on fermat, removing the need for NQE.

bsingle should be used in place of bsub for single-cpu jobs (jobs will run on fermat).

Note: if bsub is used for single-cpu jobs, a set of 4 cpus will be allocated to the job and the user will be charged for 4 cpus!

Accordingly, NQE on fermat will be withdrawn on Tuesday 6 May. Any users with concerns about this should contact csar-advice@cfs.ac.uk immediately.

Limits for Development and Debugging

Wren has a number of interactive resource limits which are intended to limit the consequences of any "runaway" processes. The default limits are such that they should be sufficient for most users most of the time but they may not be sufficient for intensive development or debugging tasks. This may be indicated by a message about the inability to fork processes or "Resource Temporarily Unavailable".

Most limits can be increased using the jlimit command (see man jlimit); in particular, the number of processes can be increased as follows

jlimit processes 16

This will allow up to 16 processes, which should be sufficient for most interactive tasks. For further information on this or any other issue related to CSAR, please contact the helpdesk.