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From: David Schwartz <davids@webmaster.com>
To: <pwaechtler@mac.com>, <linux-kernel@vger.kernel.org>
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Date: Tue, 24 Sep 2002 13:19:06 -0700
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Subject: Re: [ANNOUNCE] Native POSIX Thread Library 0.1
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>The effect of M:N on UP systems should be even more clear. Your
>multithreaded apps can't profit of parallelism but they do not
>add load to the system scheduler. The drawback: more syscalls
>(I think about removing the need for
>flags=fcntl(GETFLAGS);fcntl(fd,NONBLOCK);write(fd);fcntl(fd,flags))

	The main reason I write multithreaded apps for single CPU systems is to 
protect against ambush. Consider, for example, a web server. Someone sends it 
an obscure request that triggers some code that's never run before and has to 
fault in. If my application were single-threaded, no work could be done until 
that page faulted in from disk. This is why select-loop and poll-loop type 
servers are bursty.

	DS


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