Hi,
some programs need to do some short of busyloop. It was often
implemented as :
while (1) {
if (can_do_stuff) {
do_stuff();
}
else
//sleep a very short of time
usleep(1);
}
usleep(1) or equivalent where used instead of sched_yield, because of
some priority issue. IIRC doing sched_yield, make the process appears
like an interactive process, so it has better priority and get call more
often.
But now if high res timer are enabled, these programs while cause
something like a DOS : the context switch per second will be bigger than
500 000 and the cpu usage will be very high.
I don't know if such problem are already know, but I believe a warning
about such issues should be in the Kconfig description.
Matthieu
-
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/
