Date: Sat, 28 Oct 2000 16:51:59 -0700
From: Dan Kegel <dank@alumni.caltech.edu>
Subject: Re: kqueue microbenchmark resul
To: linux-kernel@vger.kernel.org
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> >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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