makedeltarpm

Did some detailed tests with deltarpm.

It seems that it works pretty good when making deltas of RPMs that contain mostly text files. This seems logical because text files tend not to change much and thus deltas can be created in an efficient way.

When analyzing binary files I found that it works only well when between both versions of the RPM only minor patches where applied. If you have changes that touch many parts of the source files creating a delta RPM for a package containing mainly binaries is no longer worth to do.

There is a similar result for source RPMs. If only a patch was added or removed to the source RPM package the delta RPM package is pretty small but even when only small parts of the source archive changed, the delta RPM does no longer save anything valuable because the compression for the archive completely breaks the delta algorithm.