Tag: Operating system
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Time to write a signal handler?
I am trying to execute some self-written pieces of software that require a lot of wall clock time – around three weeks. I run them on the University of York‘s compute server which is rebooted on the first Tuesday of every month, so the window for the software is limited. I have until about 7…
Adrian McMenamin
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Reasoning about a NoC
Thinking about a Network-on-Chip system and what its system software needs to do… Parallelisation is essential to efficiency – in a NoC there are a multitude of cores, but each core has only the fraction of the computational power a “traditional” unicore might be expected to have – therefore it is essential that, where possible,…
Adrian McMenamin
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Twenty years of Windows NT
Today is the twentieth anniversary of the launch of Windows NT. In fact I have been using it (I still have to – in the sense that Windows XP/7/8 are NT – on occasion) for a bit longer than that as I was a member of the NT beta programme – I even managed to…
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Computer science in the UK: in the wrong direction?
Two big thoughts strike me as a result of the literature review I have just completed for my PhD: Linux is not the centre of the universe, in fact it is a bit of an intellectual backwater; The UK may have played as big a role in the invention of the electronic computer as the…
Adrian McMenamin
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A Raspberry Pi project?
My Raspberry Pis are likely to be dispatched tomorrow. Wondering if I should use the little Plan 9 installation I plan to build as a testbed for a parallel filesystem (that I write). As preparation for next week’s literature review seminar I read about the Vesta filesystem and find it absolutely fascinating. Could we build…
Adrian McMenamin
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Plan9 on the Raspberry Pi
“Plan 9 from Bell Labs” was meant to be the successor system to Unix and like the original was designed and built by AT&Ts engineers at Bell Labs(the title is, of course, a skit on what is supposedly the best worst-ever film – “Plan 9 from Outer Space”). Plan 9 never really made it. Linux…
Adrian McMenamin
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OS/2: killed by Bill?
Here is a fascinating account of the rise and fall of OS/2, the operating system that was supposed to seal IBM’s (and Microsoft’s) global domination. Instead it flopped, being beaten by a poorer quality alternative in the form of Windows 3.0/3.1 after Microsoft pulled out. I remember when Windows NT was launched in 1993 –…
Adrian McMenamin
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Computer scientists’ lousy citation style
I am reading this book: Soft Real-Time Systems: Predictability vs. Efficiency, and I am struck, once again, by the truly lousy style of publication reference that seem to be preferred by so many computer scientists, The style used in the book appears to be that favoured by the American Mathematical Society – the so-called “authorship…
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Working set heuristics and the Linux kernel: my MSc report
My MSc project was titled “Applying Working Set Heuristics to the Linux Kernel” and my aim was to test some local page replacement policies in Linux, which uses a global page replacement algorithm, based on the “2Q” principle. There is a precedent for this: the so-called “swap token” is a local page replacement policy that…
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The binomial distribution, part 1
I think there are now going to be a few posts here which essentially are about me rediscovering some A level maths probability theory and writing it down as an aid to memory. All of this is related as to whether the length of time pages are part of the working set is governed by…
Adrian McMenamin
cartesian product ... stuff about computing mostly 