Re: [Tux3] Tux3 report: Tux3 Git tree available

From: Matthew Wilcox <matthew@wil.cx>
To: Daniel Phillips <phillips@phunq.net>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>,
	linux-fsdevel@vger.kernel.org, tux3@tux3.org,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org
Subject: Re: [Tux3] Tux3 report: Tux3 Git tree available
Date: Thu, 12 Mar 2009 06:32:30 -0600	[thread overview]
Message-ID: <20090312123230.GA14425@parisc-linux.org> (raw)
In-Reply-To: <200903120524.34150.phillips@phunq.net>

On Thu, Mar 12, 2009 at 05:24:33AM -0700, Daniel Phillips wrote:
> On Thursday 12 March 2009, Nick Piggin wrote:
> > That's interesting. Do you handle 1K block sizes with 64K page size? :)
> 
> Not in its current incarnation.  That would require 32 bytes worth of
> state while the current code just has a 4 byte map (4 bits X 8 blocks).
> I suppose a reasonable way to extend it would be 4 x 8 byte maps.  Has
> somebody spotted a 64K page?

I believe SGI ship their ia64 kernels configured this way.  Certainly
16k ia64 kernels are common, which would (if I understand your scheme
correctly) be 8 bytes worth of state in your scheme.

-- 
Matthew Wilcox				Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours.  We can't possibly take such
a retrograde step."