> >In fact, if you did leave the read queued in a daemon using select()
> >before, you'd keep looping endlessly taking all CPU and never idle
> >because there would always be read data available.
That would be a programming error on the part of the application.
Any application using a level-triggered interface like select
or poll must of course mask off events it is not interested in,
to avoid getting them endlessly. That's just 'select 101'.
> Also, level triggered notifications would also seem to cause
> multiple thread wakeups and thundering herd problems when
> there are multiple worker threads reading from the same queue.
>
> How does (?) kevent avoid this from happening?
Easy - applications which have multiple threads reading from the
same queue would use oneshot events instead of level-triggered events.
Level-triggered events are only for applications where a single thread
is reading from the queue.
- Dan
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