* Miklos Szeredi <[EMAIL PROTECTED]> wrote:
> > how come UML idled for 30 msecs here, while the workload was
> > supposed to be CPU-bound? It's not IO bound anywhere, right? No SMP
> > artifacts either, right?
>
> Yes. The UML kernel is UP, and I don't think 'date' or 'bash' want to
> do any disk I/O.
>
> Could disk I/O be blocking the tty? I think UML uses separate threads
> for these, but I don't know the details.
even if the workload is fully CPU bound externally - internally a
request to the external (CPU-bound) thread will look like an asynchonous
request - so small amounts of idle time can be within UML, legitimately.
(for the amount of time it takes for the external thread to service the
request)
30 msecs already sounds a bit excessive (this is on your T60 with
Core2Duo, right?), and 1-2 seconds noticeable latency is definitely
excessive.
Ingo
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