From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 01/45] Create a dynamically sized pool of threads for
	doing very slow work items [ver #41]
Date: Fri, 21 Nov 2008 10:17:18 -0800
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To: David Howells <dhowells@redhat.com>
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On Fri, 21 Nov 2008 10:24:00 +0000 David Howells <dhowells@redhat.com> wrote:

> Andrew Morton <akpm@linux-foundation.org> wrote:
> 
> > umm, if they're slow, why not create a kernel thread per operation? 
> > Why add the thread pool?
> 
> Because if someone does a tar of, say, a kernel tree, that'll create one
> thread per file...

OK.

>  This provides a limiter - and makes sure there are threads
> immediately available.

Those two objectives seem incompatible.  What does a caller do when the
limit has been hit?  Do the work synchronously?