On Sat, Apr 14, 2007 at 07:54:33PM +0200, Ingo Molnar wrote: > > * Eric W. Biederman <[EMAIL PROTECTED]> wrote: > > > > Thinking about it, I don't know if there are calls to schedule() > > > while switching from tty1 to tty2. Alt-F2 had no effect anymore, and > > > "chvt 2" simply blocked. It would have been possible that a > > > schedule() call somewhere got starved due to the load, I don't know. > > > > It looks like there is a call to schedule_work. > > so this goes over keventd, right? > > > There are two pieces of the path. If you are switching in and out of a > > tty controlled by something like X. User space has to grant > > permission before the operation happens. Where there isn't a gate > > keeper I know it is cheaper but I don't know by how much, I suspect > > there is still a schedule happening in there. > > Could keventd perhaps be starved? Willy, to exclude this possibility, > could you perhaps chrt keventd to RT priority? If events/0 is PID 5 then > the command to set it to SCHED_FIFO:50 would be: > > chrt -f -p 50 5 > > but ... events/0 is reniced to -5 by default, so it should definitely > not be starved.
Well, since I merged the fair-fork patch, I cannot reproduce (in fact, bash forks 1000 processes, then progressively execs scheddos, but it takes some time). So I'm rebuilding right now. But I think that Linus has an interesting clue about GPM and notification before switching the terminal. I think it was enabled in console mode. I don't know how that translates to frozen xterms, but let's attack the problems one at a time. Willy - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
