Kenneth, here's a debian bugreport about bzip2 compression
causing pretty bad timing performance for relatively little gain.

is there any chance for a toggle for this option in an upcoming 
RC version before 0.4.3 gets released?

(please keep the cc when responding so that the debian bug tracker
stays on top of the issue.)

regards
az

------- Forwarded Message
Reply-To: Sam Morris <[EMAIL PROTECTED]>, [EMAIL PROTECTED]
From: Sam Morris <[EMAIL PROTECTED]>
To: Debian Bug Tracking System <[EMAIL PROTECTED]>
Message-ID: <[EMAIL PROTECTED]>
Date: Mon, 13 Aug 2007 18:10:35 +0100

Package: duplicity
Version: 0.4.2-10.1
Severity: important

Please disable the bzip2 compression patch, or make it possible to
change the compression algorithm and level on the duplicity command
line. Currently it is hardcoded as bzip2 and level 9, which makes
Duplicity too slow to be usable on my system (a 2.4 GHz Pentium 4).

I did some comparisons between Duplicity with the bzip2 patch applied
and not applied (in which case I believe gnupg defaults to ZIP compression).

Each set of entries consists of the uncompressed size of the filesystem
on disk, then the size of an initial, full backup made with duplicity
with the bzip2 patch applied, then another initial full backup made
without the patch.

Size (MiB) Dir
---------- ---
   45      boot
    7      boot.bzip2
    7      boot.zip

 5040      root
  418      root.bzip2
  511      root.zip

 4032      var
  437      var.bzip2
  511      var.zip

10080      srv
 3925      srv.bzip2
 4167      srv.zip

The backup script took 240 minutes to back these four filesystems up
with bzip2 before I aborted it (note that it had not finished the job,
as there were still the svn and home filesystems, totalling another
13104 MiB to back up). After I reverted the patch, the script finished
in 106 minutes (this time, *including* the home and svn filesystems).

IMO, more than doubling the time that duplicity takes to run is not
worth the 8% in disk space savings from the patch. :)

-- System Information:
Debian Release: 4.0
  APT prefers stable
  APT policy: (540, 'stable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.18-4-686
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)

Versions of packages duplicity depends on:
ii  gnupg                       1.4.6-2      GNU privacy guard - a free PGP rep
ii  libc6                       2.3.6.ds1-13 GNU C Library: Shared libraries
ii  librsync1                   0.9.7-1      Library which implements the rsync
ii  python                      2.4.4-2      An interactive high-level object-o
ii  python-central              0.5.12       register and build utility for Pyt
ii  python-gnupginterface       0.3.2-9      Python interface to GnuPG (GPG)

duplicity recommends no packages.

-- no debconf information


------- End of Forwarded Message


-- 
+ Alexander Zangerl + DSA 42BD645D + (RSA 5B586291)
"I am truly free only when all human beings, men and women,
are equally free." -- Mikhail Bakunin

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