Starting in RC2 (or nightly build N20060423-0010)
org.eclipse.update.core will have support for optimizing update sites.
This support takes the form of digests and Pack200.
Pack200 is a jar compression utility
in J2SE 5.0, using it can reduce the size of a jar by about 60% depending
on its contents. However, Pack200 makes non-semantic changes to the
class files. To ensure that the bits downloaded from a packed update
site are the same bits the you get from a normal zip distribution, project
should condition their jars as part of their build process.
I have put together 2 wiki pages to
cover this issue: http://wiki.eclipse.org/index.php/Update_Site_Optimization
Projects should please take a look and
send me any feedback or questions you may have.