Darius is a 32-node cluster with InfiniBand QDR interconnections. It runs CentOS 5.4 (Linux kernel version 2.6), which is closely related to Red Hat Enterprise Linux. Its hostname is darius.mit.edu.
Performance
Notes on performance are coming soon.
Using the queue system
All programs run on Darius must use the queue system. Users can check what jobs are running using qstat
; XWindows users can try xpbs
, although load times are long. Users can submit their jobs using the qsub
command:
qsub jobscript.sh
Here is an example of a simple PBS script, which is like an ordinary BASH script, but with the addition of special #PBS directives:
#!/bin/bash #PBS -k o #PBS -N apoa #PBS -l nodes=1:ppn=4,walltime=12:00:00 #PBS -j oe cd /home/musolino/namd/apoa1 /usr/mpi/gcc/openmpi-1.4.1/bin/mpirun /share/apps/NAMD_2.7b2_Source/Linux-x86_64-OpenMPI/namd2 apoa1.namd
Notes on compiling NAMD 2.6
- Run
./config Linux-amd64-MPI.postfix
to create an installation. - The new Charm++ and NAMD 2.7 use different platform names than they did in the past(e.g.
Linux-x86_64-OpenMPI
for NAMD 2.7 and Charm++ 6.2, butLinux-amd64-MPI
for NAMD 2.6. This causes problems when looking for the Charm++ installation, so editMake.charm
in NAMD directory:CHARMBASE = /share/apps/charm-6.2.0/mpi-linux-x86_64-mpicxx
- Then edit
Makearch
in theLinux-amd64-MPI.postfix
directory as follows, by changing theCHARM=...
line:include .rootdir/Make.charm include .rootdir/arch/Linux-amd64-MPI.arch CHARM = $(CHARMBASE) NAMD_PLATFORM = $(NAMD_ARCH)-MPI include .rootdir/arch/$(NAMD_ARCH)$(NAMD_SUBARCH).base
- Try
make
in the installation directory.
Other notes
Using the Mac OS 10.6 X11 client, XWindows is working, with small utilities like xcalc and xpbs, and with VMD 1.8.7. VMD performance seems sluggish, however. Note: when connecting with "ssh -X", starting VMD consistently leads to a crash of the X11 client. Connecting with "ssh -Y" (which disables X11 security protocols, for trusted connections) works instead. This problem has occurred with other computers in the past, and it's not clear whether this is a bug in VMD, the X11 installation on the cluster, or the Mac OS 10.6 X11 client.