Darryl Gove's blog

Multi-core Expo

My paper "Strategies for improving the performance of single threaded codes on a CMT system" has been accepted for the Multi-core Expo in Santa Clara. I'm not sure when I'll be presenting; the agenda should be available soon.

Posted at 11:49AM Feb 18, 2008 by Darryl Gove in Sun  | 

Win $20,000!

Sun has announced a Community Innovation Awards Programme - basically a $1M of prize money available for various Sun-sponsored open source projects. There is an OpenSPARC programme, and the one that catches my eye is $20k for:

vi. Best Adaptation of a single-thread application to a multi-thread CMT (Chip Multi Threaded) environment

My guess is that they will expect more than the use of -xautopar -xreduction or a few OpenMP directives If I were allowed to enter (unfortunately Sun Employees are not) I'd be looking to exploit the features of the T1 or T2:

• The threads can synchronise at the L2 cache level - so synchronisation costs are low
• Memory latency is low

The upshot of this should be that it is possible to parallelise applications which traditionally have not been parallelisable because of synchronisation costs.

Funnily enough this is an area that I'm currently working in, and I do hope to have a paper accepted for the MultiExpo.

Posted at 12:17PM Jan 31, 2008 by Darryl Gove in Sun  | 

Multi-threading webcast

A long while back I was asked to contribute a video that talked about parallelising applications. The final format is a webcast (audio and slides) rather than the expected video. This choice ended up being made to provide the clearest visuals of the slides, plus the smallest download.

I did get the opportunity to do the entire presentation on video - which was an interesting experience. I found it surprisingly hard to present to just a camera - I think the contrast with presenting to an audience is that you can look around the room and get feedback as to the appropriate level of energy to project. A video camera gives you no such feedback, and worse, there's no other place to look. Still I was quite pleased with the final video. The change to a webcast was made after this, so the audio from the video was carried over, and you still get to see about 3 seconds of the original film, but the rest has gone. I also ended up reworking quite a few of the slides - adding animation to clarify some of the topics.

The topics covered at a break-neck pace are, parallelising using Pthreads and OpenMP. Autoparallelisation by the compiler. Profiling parallel applications. Finally, detecting data races using the thread analyzer.

Posted at 02:25PM Nov 26, 2007 by Darryl Gove in Sun  |  Comments[1]

Book on OpenMP

Interesting new book on OpenMP available. I've worked with both Ruud and Gabriele. I regularly see Ruud when he makes his stateside trips, and Gabriele used to work in the same group as I do before she moved from Sun. I've recently had a number of entertaining conversations with Ruud comparing the writing and publishing processes that we've been working through.

Posted at 04:07PM Sep 28, 2007 by Darryl Gove in Sun  |