Bug 145685

Description David Williams 2006-06-06 23:32:35 EDT

This is an "info" bugzilla only, to document the size of Callisto (as of RC4) and the effects of using Pack200. I will attach an excel spreadsheet that contains the "raw data" that lead to this summary, in case anyone else want to play with them, or do a more detailed analysis. 

There are 645 jars "available" for download (some are platform specific, so no one would ever download them all -- though I'll act like they would for some of the following summaries). 

The total size of all those 645 jars is 194 MBytes. (So, imagine, that's what would be downloaded if pack200 not available, and someone needed them all). 

I think only the Eclipse Project and the WTP project have conditioned their jars (as of RC4) which leads to about half of those jars having packed versions available. 

The total size of all the packed (.gz) files is 47 MBytes. 
The total size of the jars that correspond to these gz files is 107 MBytes. 

This means that "packing" in general, on average, produces .gz files that are 44% the size of their corresponding jars. 

If instead you take as the-total-to-include all the files that would need to be downloaded, the packed version is 70% of that total (so, if most users have 'unpack' available, and if most users used update manager, you can thank the WTP and Eclipse Projects for saving 30% bandwidth in the upcoming release :) But if everyone did it, the saving would be about double that! Hmmm, what's that translate into rented bandwidth costs :) 

It is very interesting that on a jar by jar basis, the reduced size varied everywhere from 20% to 90% of the original jar (with the 44% being a real-life-in-practice average). As would be expected, "doc" plugins did not compress well, and very small code plugins did not compress well. 

Hope everyone finds these interesting.