A chiller in the air.

The December chill is warming up

Posted on 11 December 2014 by Thomas Green

We are now halfway through the planned works on the datacentre and on the whole everything is currently going as planned.  Thankfully the weather has been fairly good to work outside and the main event being the new chillers were delivered over the weekend of the 6th/7th.  All talks of “weather bombs” or more technically
Read more

Temporary cooling

The December chill

Posted on 3 December 2014 by Thomas Green

For users of ARCCA services, December is an important month due to our datacentre having been mostly shutdown whilst work is performed on the cooling infrastructure and other internal changes. This has required a disruption in our services but in the long-term provide a more resilient cooling infrastructure and space to house more hardware. Reasons
Read more

Bashing those script bugs

Posted on 20 November 2014 by Thomas Green

Recently we had a user report a problem where they had managed to start copying the complete filesystem of a compute node into their home directory. Fortunately for us we had setup quotas on our users home space so it stopped when it filled up their quota but it seemed it was all due to
Read more

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
Read more

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
Read more

Performant Python with Intel MKL

Posted on 15 October 2014 by Thomas Green

ARCCA have recently been helping a research group at Cardiff University to benchmark their code. The code was based on Python and had many options to perform FFT analysis. One particular option was to use the Intel MKL directly within the Python code. This was particularly useful since the MKL would have had optimisations for
Read more

Postive performance with C++

Posted on 1 October 2014 by Thomas Green

Recently a researcher has come to us with a performance issue in their code.  The code was written in C++ and was taking a very long time to run – reaching a limit on the time a job can run within our scheduler. Profile of the culprit First thing to do when given a task
Read more

Scoping out ARCCA

Posted on 11 September 2014 by Thomas Green

If you have read the previous posts you will see that they can be quite technical and a couple of readers have mentioned they would like to read about something more relevant to non-technical users.  I hope to make this blog accessible to a wide audience and make people aware of some of the work
Read more

Excelling in R

Posted on 1 September 2014 by Thomas Green

Recently we have helped researchers wanting to perform a large analysis of data that was in an Excel spreadsheet. We had over 70,000 rows and around 20 columns which required lots of conditional summing and checks to be performed. After trying to use Excel to perform the analysis on my Mac it seemed the conditional
Read more

Arguments cause headaches

Posted on 27 August 2014 by Thomas Green

Having spent some time taking a look at a problem for a researcher where a program would quit with the dreaded: Segmentation fault (core dumped) It led to a common problem of argument chasing. Fortran arguments Fortran (unlike C) by default passes arguments by memory address (i.e. pointers).    This speeds up performance since it does
Read more