Messages in this thread |  | | Date | Sat, 22 Sep 2001 15:14:53 +0200 | From | Andrea Arcangeli <> | Subject | Re: ksoftirqd? (Was: Re: [PATCH] Preemption Latency Measurement Tool) |
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On Sat, Sep 22, 2001 at 02:56:58PM +0200, Roger Larsson wrote: > Hi, > > We have a new kid on the block since we started thinking of a preemptive > kernel. > > ksoftirqd... > > Running with nice 19 (shouldn't it really be -19?) > Or have a RT setting? (maybe not since one of the reasons for > softirqd would be lost - would be scheduled in immediately) > Can't a high prio or RT process be starved due to missing > service (bh) after an interrupt?
It cannot be starved, if ksoftirqd is never scheduled the do_softirq() will be run by the next timer irq or apic_timer irq.
> This will not show up in latency profiling patches since > the kernel does what is requested... > > Previously it was run directly after interrupt, > before returning to the interrupted process...
It is still the case, that's also the common case actually.
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