Closure of the CSAR Service

As most of you will be aware the CSAR service ceased operation on Friday 30 June 2006 at the end of its current contract. For those of you with projects that run beyond this date, the Research Councils will be responsible for providing access to alternative resources. PI's should liaise with the relevant research council regarding the transfer of their CSAR projects if applicable. All users who currently have accounts on the CSAR systems will be responsible for transferring their data elsewhere.

Key Dates

• The service closed at midnight on 30th June 2006.
• No jobs submitted to the batch queues after this time will be accepted.
• Interactive login to Wren will be available for a limited period for the removal of data.

Transferring Data

• All data should be removed from the CSAR systems as soon as possible after 30th June, or deleted if not required.
• Any data not removed from the system will be lost.
• The primary mechanism for moving data will be sftp or scp.
• Please view the following page for further information on moving data.

Data Compatibility between Newton and Other Systems

The default data written out from any program on Newton is that which matches its storage order in memory. Newton uses a little-endian format, which is not necessarily compatible with other systems. As CSAR closes, you will need to move your data from CSAR onto another system data format.

What you need to do to solve the problem depends on what you use to write data out. There are numerous options in FORTRAN, the easiest way is to use the environment variables to change the format in which you want to output your data. For example, the following bash/ksh command will set Fortran (8.1 and 9.0 compilers) unit number 60 to output data in a form that can be read on IBMs (including HPCx).

If you now run a code all data, using unit number 60, will be interpreted as being read or written for an IBM. There are other options which are discussed fully in the man pages.

There are no such options for c/c++ programs where you will need a converter program or to use a more portable format.

In all cases you may wish to consider:

• Moving to a more portable neutral format. Neutral data representations such as HDF, NetCDF and XDR thus alleviating all portability issues.
• Using the environment variables to adjust the way in which machine interprets the data.
• Write a conversion program

Porting Codes from CSAR to HPCx

A one-day workshop was given on the differences between the two systems. The course took place on Thursday 25 May 2006; tutors were experienced members of the CSAR and HPCx staff.

For further details of this workshop, and links to the presentations, please go to: http://www.hpcx.ac.uk/support/training/HPCxCSARPorting.html