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From: Jesse Pollard <pollard@admin.navo.hpc.mil>
To: Larry McVoy <lm@bitmover.com>, Jeff Garzik <jgarzik@pobox.com>
Subject: Re: ANNOUNCEMENT: Squashfs released (a highly compressed filesystem)
Date: Wed, 30 Oct 2002 08:53:09 -0600
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On Tuesday 29 October 2002 10:11 pm, Larry McVoy wrote:
> > A r/w compressed filesystem would be darned useful too :)
>
> mmap(2) is, err, hard.  Not impossible, it means the file system has to
> support both compressed and uncompressed files, but it's interesting.

You can also think of it as a step toward a hierarchical filesystem with the
files:
	1. uncompressed (with uncompressed inode)
	2. compressed on line (real disk space allocated)
	3. compressed nearline (only compressed inode on disk, with a
	reference to offline storage)

Obviously this is only for very large filesystems (we have one FS that
is currently between 100-200 TB in size when you include the migrated
storage).
-- 
-------------------------------------------------------------------------
Jesse I Pollard, II
Email: pollard@navo.hpc.mil

Any opinions expressed are solely my own.
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