The Nvidia CUDA development kit has been updated to version 4.1.
DAS-4/ASTRON has succesfully correlated three hours of data coming from 288 LOFAR antennas, possibly setting a world record.
The GPU page documents how the OpenCL implementations on DAS-4 can be used.
DAS-4/VU achieved the 16th place on the Graph500 list. A very good result, as all higher-ranked systems are significantly bigger.
DAS-4 supports the OpenNebula package for Cloud computing.
If you are a faculty member or student at the participating universities, you may request a login account on the DAS-4 system by sending mail to das-account@cs.vu.nl.
The DAS-4 clusters do not form one seamless whole. In particular, the password administration is done per site: the master copy of the password files is at fs0.das4.cs.vu.nl, and users should only change their password there. The password files at the other sites will be regularly updated with the version at the master site.
The file systems at different sites are completely separate, so it
will be necessary to transfer the files between the home directories
manually (e.g., by means of scp), or by using Grid software that does
this transparently for you.
Besides the home directories, the directory /var/scratch of the file server is also mounted on each DAS-4 node. You can use the subdirectory /var/scratch/<userid> for temporary bulk storage during or between jobs. In case you need space for temporary files on each node separately, you can use /local/<userid>. Please empty /var/scratch/<userid> and /local/<userid> when you no longer need the space.
Problem reports, e.g., missing software or documentation or apparent hardware failures, should be sent to das-sysadm@cs.vu.nl.
For account related support (e.g., if you ran out of diskquota or you forgot your password) please send mail to das-account@cs.vu.nl.
Access to the DAS-4 is possible by logging in to the DAS-4 fileserver at one of the participating sites using ssh (secure shell).
The DAS-4 head node (fileserver) and compute nodes are named as follows:
| Cluster | Head node | Compute nodes |
|---|---|---|
| VU | fs0.das4.cs.vu.nl | node001-node075 |
| LU | fs1.das4.liacs.nl | node101-node116 |
| UvA | fs2.das4.science.uva.nl | node201-node218 |
| TUD | fs3.das4.tudelft.nl | node301-node332 |
| UvA-MN | fs4.das4.science.uva.nl | node401-node436 |
| ASTRON | fs5.das4.astron.nl | node501-node523 |
Users will typically login to one of the DAS-4 file servers, develop software there, and start the parallel applications on a subset of the compute nodes. To avoid people getting in each other's way on the compute nodes, every DAS-4 user is required to use the cluster startup and reservation commands described in this section.