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Date: Wed, 18 Jul 2007 13:16:24 +1000
From: "Lindsay Roberts" <lindsay.roberts.os@gmail.com>
To: "Matt Mackall" <mpm@selenic.com>
Subject: Re: [PATCH] fs: Add romfs version 2
Cc: "Andrew Morton" <akpm@linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>, celinux-dev@tree.celinuxforum.org
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On 7/18/07, Matt Mackall <mpm@selenic.com> wrote:
> > > * Adds new derivative of romfs filesystem (rom2fs) with
> > >   block aligned regular file data to bring performance
> > >   parity with ext2/3. This is about 225% of the read
> > >   speed of the existing romfs.
>
> Doesn't that make these filesystems much bigger? By, on average, .5k
> per file? Or, if I'm understanding things correctly, ~1k?

Yes, my experience has been that it has been almost chillingly close
to .5k per regular file increase in partition size. I know in
applications in which size is utterly critical this may be slightly
unattractive, but in cases where romfs is chosen for its byte
reproducibility and read-only nature the size/performance tradeoff is
fairly advantageous.