This is the homepage of Bob Wilkinson. It is running under Debian GNU/Linux and was hosted on a Sheeva Plug, but now at kimsufi

I have been writing some code for my parallella computer. Initially, I modified the example dot product and saw that I could split a vector into parts and process the parts (this being via a scatter/gather process, or a map/reduce idiom). Since the vector I was working with intially was small, I observed a slow-down in execution time; the overheads of the splitting, distribution of data to the nodes of the epiphany co-processor, running the code and gathering the results far outweighed just running the code on the host processor sequentially. When I increased my problem size, I did see some speed up (as expected). Other problems of a similar nature can be parallelised in the same way, however, performance gains are usually difficult to achieve, and the technical complexity is insufficient to make the problem interesting.

I spent some time thinking of a problem which would be sufficiently interesting to me. I have, for a number of reasons, decided that I should write a parallel version of the Game of Life.

I have just uploaded my disk de-duplication software to github, so if you want to squash the contents of a backup disk by consolidating the duplicates, please try it. I have used it on Linux - if you are brave enough to use it on anything else, please let me know! It is a perl script, so it should work elsewhere.

I have been trying some of the problems at and my solutions to the first n are here. I also looked at too and wrote the first problem in assembly language and forth, too. I wanted to write forth because of the fignition computer and needed to remind myself how to code in forth - it has been a long time. ARM assembly language is an on-going interest. I know that I can improve so I practise more.

I have a short introduction to assembly programming on the ARM processor. I was asked How much faster is assembly language on the ARM.

A long time ago (around 2000-2001) I wrote a Perl interface to a C program for converting music on vinyl records to digital formats..

I have written Perl interfaces to some C disassemblers : X86::Disasm and X86::Udis86

Here is a simple tutorial showing how to call C code from Perl code.

I usually have Mr Perry and his BlackArkNuggets to listen to.

I also listen weekly to On The Wire and Blowin and have recently re-discovered my youth with John Peel