Software

Dedicated to software topics.

Lock

Finding the key to your locks

Posted on 24 November 2016 by Thomas Green

Websites can be very useful for HPC to allow easier access. Recently we had an issue with a website we use and learned a few things on the way. Know your users A website has been running fine for a number of months – and building up a user base. However we recently hit an
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RAF Roundel

Mods and rockers

Posted on 29 September 2016 by Thomas Green

Modules are used on many supercomputers since it allows multiple versions of software to be easily chosen to be loaded into a users environment. We would now like to show how modules work on our supercomputer since we apply some tricks to try and make maintaining them easier and make them “rock” even more. What
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Image of restart icon

The art of restarting

Posted on 27 April 2016 by Thomas Green

Limits on runtimes Running jobs on a supercomputer can sometimes involve letting the job run for a long time. A long time in this instance is longer than the default expected maximum runtime for a particular type of job. At Cardiff we have 2 types of jobs which we have setup our supercomputer for. Serial
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Developing Software

Posted on 25 April 2016 by Andrew Williams

The next ARCCA drop in session at the Queen’s buildings will be occuring this Thursday, the 28th April at 2pm in the Trevithick library room 1.15. This is up the stairs from the Trevithick reception, in through the main library entrance and straight ahead until you get to the study rooms on the left. The
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Drop-in session at the Queen’s Buildings

Posted on 24 February 2016 by Andrew Williams

This Thursday (the 25th February), ARCCA will be holding a drop-in session in the Trevithick library room 1.15, from 2pm to 3.30pm. These drop-in sessions are an opportunity for the community to meet up with ARCCA in order to ask us questions, suggest ideas, or plead for help! As part of this initial session at
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Rose and Managing Workflows

Posted on 9 December 2015 by Andrew Williams

How would you like a tool that would allow you to: Write and maintain workflows more efficient and sophisticated than an existing job submission script. Create dependency trees of tasks that will run at the click of a button, with automatic optimisation so that multiple tasks may be run in parallel. Revision control your tasks
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Perls of wisdom

Posted on 9 November 2015 by Thomas Green

It has been a long summer and it is time again to create a little post for a recent encounter on our supercomputer. Errors in Perl Perl is a common language which is very common within the Genomic communnity. Recently we had an interesting Perl issue where a job would just run for its maximum
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Rating value

Summarising job performance

Posted on 13 August 2015 by Thomas Green

Recently we have implements an automatic job summary which is printed at the end of a user’s job that run on our supercomputer at Cardiff University. These job summaries are to help the user understand what impact the job has had and how to improve future jobs – just like energy efficiency ratings. This post
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United nations assembly.

Research seminar – Accelerating computing

Posted on 2 July 2015 by Thomas Green

Using accelerators such as GPUs and Intel Phi technologies are becoming a popular method to extend the performance of certains codes. ARCCA is holding a research seminar which covers this topic. All are welcome to attend, even if you are not planning to use the technologies its is great to see the cutting-edge research Cardiff
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Iceberg

Floating in numbers

Posted on 26 June 2015 by Thomas Green

Just like an iceberg, floating point numbers can have hidden danger lurking just under the surface. A recent email through a mailing list reminded me about the subtlties of handling floating point numbers. Floating point numbers are represented by mantissa*(base**exponent), see floating point numbers. There are many occassions where programmers may forget that floating point
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