Date: Mon, 30 Oct 2000 10:55:38 -0800
From: John Gardiner Myers <jgmyers@netscape.com>
Subject: Re: Readiness vs. completion (was: Re: Linux's implementation of
 poll()not scalable?)
To: dank@alumni.caltech.edu
Cc: linux-kernel@vger.kernel.org
Message-id: <39FDC42A.CD9C3D12@netscape.com>
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Dan Kegel wrote:
> IMHO you're describing a situation where a 'completion notification event'
> (as with aio) would be more appropriate than a 'readiness notification event'
> (as with poll).

I've found that I want both types of events, preferably through the same
interface.  To provide a "completion notification event" interface on
top of an existing nonblocking interface, one needs an "async poll"
mechanism with edge-triggered events with no event coalescing.

You are correct in recognizing NT completion ports from my description. 
While the NT completion port interface is ugly as sin, it gets a number
of performance issues right.

> And, come to think of it, network programmers usually can be categorized
> into the same two groups :-)  Each style of programming is an acquired taste.

I would say that the "completion notification" style is a paradigm
beyond the "readiness notification" style.  I started with the select()
model of network programming and have since learned the clear
superiority of the "completion notificatin" style.
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