HPC

Dedicated to High Performance Computing.

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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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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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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Making a network work

Posted on 19 March 2015 by Thomas Green

We recently installed new nodes into our supercomputer. As part of the process we have to run tests to assess the new nodes. Since this was an extension to the existing infrastructure there were limits on how many high-speed links (or Infiniband (IB) connections) could be wired in, and the use for the nodes would
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DRMAA

Working with DRMAA

Posted on 2 March 2015 by Thomas Green

Anyone who might have read earlier posts might have come across previous post on Galaxy. This used DRMAA to submit jobs when using a PBS Pro as a job scheduler. However recent issues whilst we upgraded our systems uncovered some unexpected issues with DRMAA. Going native with DRMAA First issue is with a feature of
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Breaking down walls

Posted on 10 November 2014 by Thomas Green

The fall of the Berlin Wall happened 25 years ago and I thought a symbolic look at how we try and break our own walls would be quite appropriate. Creating the creative economy The Creative Industries has gained a lot of traction recently within the UK with much emphasis on TV and film having been
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Portal to a new Galaxy

Posted on 24 October 2014 by Thomas Green

Within the ARCCA team we are investigating ways we can open up high-performance computing (HPC) to a wider audience. I should add this is not just an issue within ARCCA but a more general trend across HPC organisations. The name for website which provide easier access to HPC are called Portals or Gateways. The Extreme
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