Date: Wed, 16 Nov 2005 16:25:16 -0800
From: Andrew Morton <akpm@osdl.org>
To: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: theonetruekenny@yahoo.com, linux-kernel@vger.kernel.org
Subject: Re: mmap over nfs leads to excessive system load
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Trond Myklebust <trond.myklebust@fys.uio.no> wrote:
>
> The accompanying NFS patch makes use of this in order to figure out when
>  to flush the data correctly.

OK.  So with that patch, nfs_writepages() may still leave I/O pending,
uninitiated, yes?

I don't understand why NFS hasn't been BUGging as it stands at present.  It
has several end_page_writeback() calls but no set_page_writeback()s. 
end_page_writeback() or rotate_reclaimable_page() will go BUG if the page
wasn't PageWriteback().
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