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From: Robert Watson <rwatson@FreeBSD.org>
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To: Julian Elischer <julian@elischer.org>
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Cc: Paul Allen <nospam@ugcs.caltech.edu>, Lev Serebryakov <lev@freebsd.org>,
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Subject: Re: KSE, libpthread & libthr: almost newbie question
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On Fri, 27 Oct 2006, Julian Elischer wrote:

> there is class of problems (e.g. some java programs) that have THOUSANDS of 
> threads, each representing an active aspect of some object. How do you put 
> an rlimit on that without either 1/ stopping the program from working or 2/ 
> allowing thousands of threads to exist but not screwing other users.

Does the JVM actually expose thousands of threads to the OS, or does it 
actually do its own M:N threading internally based on its execution model? 
My impression is the latter, exposing threads to the OS only when it needs 
them to consume kernel or CPU resources.

Robert N M Watson
Computer Laboratory
University of Cambridge