Computer simulation, programming, software, technology, research, and more (since 2007)
In a funny coincidence, I published an article at SCDSource.com about the need for cycle-accurate models for virtual platforms on the same day that ARM announced that they were selling their cycle-accurate simulators and associated tool chain to Carbon Technology. That makes one wonder where cycle-accuracy is going, or whether it is a valid idea at all… is ARM right or am I right, or are we both right since we are talking about different things?
Let’s look at this in more detail.
The Register has a few podcasts in addition to their website, and the one called “Semicoherent Computing” has turned into a very nice series of interviews with interesting people from the computer industry. I recently listened to their interview from September 2007 with David Ditzel of Transmeta fame. He had a lot to say about the history of computing, as well as interesting things on where computing is going. Well worth a listen! Particular interesting highlights…
Continue reading “David Ditzel Interview at The Register/Semicoherent Computing”
PC Perspective writes in its IDF writeup about Intel’s upcoming Dunnington device with six cores on a die. Another break from the 2-4-8 powers-of-two progression. Feels oddly refreshing, even if it is really nothing very strange about it. Just like AMDs triple-core.
Sometimes it is very reassuring that certain things do not work when tested in practice, especially when you have been telling people that for a long time. In my talks about Debugging Multicore Systems at the Embedded Systems Conference Silicon Valley in 2006 and 2007, I had a fairly long discussion about relaxed or weak memory consistency models and their effect on parallel software when run on a truly concurrent machine. I used Dekker’s Algorithm as an example of code that works just fine on a single-processor machine with a multitasking operating system, but that fails to work on a dual-processor machine. Over Christmas, I finally did a practical test of just how easy it was to make it fail in reality. Which turned out to showcase some interesting properties of various types and brands of hardware and software.
Continue reading “Dekker’s Algorithm Does not Work, as Expected”
The book “Multicore Programming – Increasing Performance through Software Multithreading” by Shameem Akhter and Jason Roberts is part of a series of books put out by Intel in their multicore software push. In case you have not noticed, Intel has a huge market push currently where they give seminars, publish articles and books, and give curricula to universities in order to get more parallel software in place. I read this book recently, and here is a short review.
Continue reading “Book Review: Intel’s Multicore Programming Book”
Intel has a really neat tool on their homepage: the Intel ARK — Automated Relational Knowledgebase. It is a horrible name for a brilliant tool: it lets you search for processor names, codenames, chipsets, and jump around in a database of processor variants, compatible chipsets, feature lists, and more. Not that I care particularly about Intel chips, but the tool is something everyone selling silicon devices should copy. Being able to quickly figure out just what is inside a certain device (and what is not), and finding related devices and compatible chips is just brilliant for curious people, customers, and supporting services.
Please, everybody else?
The SICS Multicore Day August 31 was a really great event! We had some fantastic speakers presenting the latest industry research view on multicores and how to program them. Marc Tremblay did the first presentation in Europe of Sun’s upcoming Rock processor. Tim Mattson from Intel tried hard to provoke the crowd, and Vijay Saraswat of IBM presented their X10 language. Erik Hagersten from Uppsala University provided a short scene-setting talk about how multicore is becoming the norm.