On Fri, 2011-04-15 at 23:06 -0700, JD wrote: > On 04/15/2011 10:58 PM, Jonathan Dieter wrote: > > On Fri, 2011-04-15 at 22:33 -0700, JD wrote: > >> On 04/15/2011 09:04 PM, Andre Robatino wrote: > >>> http://cedarandthistle.wordpress.com/2009/11/06/on-binary-delta-algorithms/ > >> Read the article and parts of the thesis. > >> So, the final version of the algorithm > >> still remains with the University of Oxford?? > >> > >> I downloaded the bsdiff srpm for fc15 and built it. > >> > >> I then used it to diff > >> -rwxr-xr-x 1 root root 3699072 Feb 6 23:09 > >> /boot/vmlinuz-2.6.35.11-83.fc14.i686 > >> vs > >> -rwxr-xr-x 1 root root 3702144 Mar 31 15:26 > >> /boot/vmlinuz-2.6.35.12-88.fc14.i686 > >> and the resulting patch > >> -rw-r--r-- 1 root root 3554921 Apr 15 22:17 > >> vmlinux-2.6.35.11-83--2.6.35.12-88.patch > >> > >> So, you can see that the patch is almost the same size as the files diffed. > >> > >> Obviously, version 4.3-8 does not contain the unpublished optimizations > >> that Colin Percival mentions in his thesis. > > A couple of things: > > > > 1. vmlinuz is compressed and it's essentially useless to delta > > compressed files without uncompressing them first. > > 2. We use the program deltarpm to make deltas between rpms. > > Deltarpm uses a modified bsdiff algorithm as well as the add > > block enhancements mentioned in my blog post. > > > > Jonathan > So, deltarpm actually uses the enhanced (i.e. modified) algorithm that > Colin Percival mentions in his thesis, or is it from a different author?
Yes, though a different person wrote the code. Jonathan
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