Roland McGrath <[EMAIL PROTECTED]> writes: > As far as I know, the Hurd has never been tested on a multiprocessor. > Since the microkernel always does preemptive scheduling, in the abstract > there is almost no way for the Hurd to tell whether kernel threads are > purely software or are running on multiple real processors, and there is > nothing whatsoever it does that is supposed to care. But since it hasn't > been tested, I have to assume there are bugs that will only show up on real > SMP hardware.
Actually, it is possible to tell, at least on the Intel hardware. >From my brief, unpleasant) experience using NT SMP/kernel threads, SMP leads to many more headaches. One example was that integer reads/writes weren't atomic. Not that ths matters unless you're (like I was) using sloppy locking (I was in a hurry, ok? :). So I don't eexpect the Hurd will have problems, but it's entirely possible. I'd really like to see the Hurd running on SMP hardware (just wish I'd been able to afford some). Andrew
