On the contrary. If the disk request queue is plugged and the task
which is submitting writeback is preempted, the IO system could
remain artificially idle for hundreds of milliseconds while the CPU
is off calculating pi. This is one of the reasons why I converted
the 2.5 request queues to unplug autonomously.
But that is speculation as well - I never observed this aspect to be
a real problem. Probably, it was not.
Substantiation of your claim requires quality testing and a plausible
explanation. I do not believe we have seen either, OK?
> Read:
> http://linuxdevices.com/articles/AT6106723802.html
I did, briefly. It appears to be claiming that the average scheduling
latency of the non-preemptible kernel is ten milliseconds!
Maybe I need to read that again in the morning.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/