Latency and overall performance says the common one. Especially as adding
to a wait queue is very very cheap
> At least, as soon as the first fd shows that it's ready for I/O, take us
> off all the wait queues and stop putting us on them. But please stop blaming
> the poll API for an implementation problem that is _not_ inherent in the
> API.
That seems to violateSuS. It has to report the state of all fd's. The
API is the problem.
> > Signal based I/O is definitely the right approach for scaling
> I still find this very hard to believe. How can one fast pass through poll
> (assuming a smarter implementation) be less efficient than the OS sending me
> 5,000 signals? That strikes me as an incredible claim.
Benchmark it. Or for that matter just apply common sense. A signal
delivery is O(1) with the number of events not O(N) (n=fdcount). A signal
has wake one properties too.
People have tried this model. It works. VMS AST's are very similar in concept.
Alan
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