[CentOS-devel] deltarpm and presto for centos

Mon Nov 16 12:06:51 UTC 2009
Jonathan Dieter <jdieter at gmail.com>

On Mon, 2009-11-16 at 12:52 +0100, Ralph Angenendt wrote:
> Am 16.11.09 11:26, schrieb Jonathan Dieter:
> > On Mon, 2009-11-16 at 11:06 +0100, Ralph Angenendt wrote:
> >> Like: Updates for 5.x are x GB without prestom but only y GB with
> >> presto? How much additional space will be required on the mirrors? Other
> >> things which might be needed to make a decision?
> > 
> > In my presto-enabled CentOS 5.4 i386 mirror, the deltarpms take up 91MB
> > (compared to 1.2GB for the actual RPMS).
> Hmmm. 5.3 would be a bit more interesting, as it had a "complete round"
> of updates, but ...

Unfortunately, I cleared out all of the 5.3 deltarpms when I updated to
5.4.  I did do deltarpms from 5.3+updates (or was it just 5.3, I'm
afraid I don't remember) to 5.4, and it came to 151MB of deltarpms.

> So would you say that ~10% seems like a workable rule of thumb?

In Fedora, it's much larger (closer to 25% - 30%), but I think that has
to do with the fact that in my mirrors, I throw away any deltarpms that
save less than 50%, while Fedora seems to keep all generated deltarpms.
Also, Fedora goes through far more updates in a cycle (and the updates
tend to have bigger changes) than CentOS.

I just wish I had kept the 5.3 deltarpms so I could give you a better

> Another question: Can those repos be mixed or do I have to have an
> "updates/" and an "updates.presto/" directory?

Normally, the deltarpms are dumped into "updates/drpms/", while the
regular rpms stay in "updates/".  One of the most important requirements
for yum-presto is that it falls back on regular rpms if the preferred
deltarpm doesn't exist, so it's built on top of the regular yum
procedure rather than replacing it.

Hope that clarifies things.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part
URL: <http://lists.centos.org/pipermail/centos-devel/attachments/20091116/ba06f4f1/attachment-0005.sig>