[Server-devel] RW Compressed FUSE FSs? (Re: XS - XO archiving and backup)

[Bill Bogstad]

On Mon, Nov 10, 2008 at 2:34 PM,  <pgf at laptop.org> wrote:
> martin wrote:
>  > On Mon, Nov 10, 2008 at 11:17 AM, Tomeu Vizoso <tomeu at tomeuvizoso.net> wrote:
>  > > I would get a real journal and check for real which is the
>  > > compressibility of the data that is actually there.
>  >
>  > On a test machine with a good cross-section of activity documents, I
>  > gzipped all the files in the datastore directory. Only 6% storage
>  > savings according to the gzip stats - higher if I only look at the
>  > metadata files (avg 12%). Several files had negative compression
>  > ratios.
>  >
>  > So your suspicions seem correct - compression is a marginal win at
>  > best for ds-backup.
>
> i assume we're already doing duplicate checks in order to avoid
> storing the same present-on-every-client executable N times, right?

Ds-backup only backs up files in the XO users journal so except for
downloaded *.xo bundles there won't be any?? 'executables'.  i.e. You
won't get the large reduction that you see in backups of Windows/Linux
clients OS images where 4 or 5 gigs of storage is replicated across
all of the machines you are backing up.

Bill Bogstad