Messages in this thread | | | Subject | Re: 2.4.4 sluggish under fork load | Date | Tue, 1 May 2001 21:34:55 +0100 (BST) | From | Alan Cox <> |
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> OK I found the explanation now. The reason ksoftirqd was deadlocking on > me without the explicit clear of SCHED_YIELD in p->policy is because a > softirq event was pending at the time of the first kernel_thread() and > then while returning from the syscall it was so taking the ret_from_irq
Oh boy.
> > + current->policy |= SCHED_YIELD; > > + current->need_resched = 1; > > + } > > Alan, the patch you merged in 2.4.4ac2 can fail like mine, but it may fail in > a much more subtle way, while I notice if ksoftirqd never get scheduled > because I synchronize on it and I deadlock, your kupdate/bdflush/kswapd > may be forked off correctly but they can all have SCHED_YIELD set and > they will *never* get scheduled. You know what can happen if kupdate > never gets scheduled... I recommend to be careful with 2.4.4ac2.
Change merged for -ac3. Nice debugging
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