On Mon, Jan 24, 2011 at 12:09:19PM +0200, Shachar Shemesh wrote: > Don't get me wrong. Had I still been a student, I'd take that class > in a blink of an eye. I'm just worried that students will take it > without realizing just how much work it is.
We intend to clarify up front that this is going to require serious work, and anyone who isn't up to it, is welcome to drop the class. > >>Is the platform Intel, or something saner (say, ARM, PPC, MC680x0 > >>or, come to think of it, just about any other CPU)? > >The platform is good ol' x86 because (1) everyone has one and (2) > >whatever you learn in this course will be immediately applicable in > >the real world. > It also has a horrific assembly, as well as a "too many layers" MMU > which revives that segmented addresses everyone have been working so > hard to forget ever existed. Undoubtedly x86 won't win any points in an ISA beauty contest, but it does what it does well, segmentation can be useful even today (see for example the original Xen protection model on 32 bit or vx32), and its hierarchical page table model is the one the students are familiar with and is heavily explored in the research literature. > ARM, on the other hand, is (1) reasonable and straight forward > assembly, and even reasonable MMU (2) has readily available > emulators for all platforms and (3) is also fairly immediately > applicable in the real world, arguably more so than X86. It also lags quite a bit behind x86 in various interesting ways, if you come from the server space: virtualization support for example, or efficient page table design. Not to mention that ARM apparently is following in the x86 foot steps -- didn't they just introduce the horrors of PAE? > Let's put it this way. The chances a CS graduate will be asked to > write an ARM based BSP are much higher than the chances she'll be > asked to write an X86 based one. Maybe. But the chances he'll end doing kernel hacking on x86 are higher, especially if he lands eventually in our research group. Cheers, Muli _______________________________________________ Haifux mailing list Haifux@haifux.org http://hamakor.org.il/cgi-bin/mailman/listinfo/haifux