threads / discuss / 30336

how to analyze binary delta compression

Subject: how to analyze binary delta compression

## tl;dr

2 messages between Apr 25, 2012 and Apr 25, 2012.

replies: 1people: 2as markdown or json

Neal Kreitzinger· Apr 25, 2012, 21:15 UTC · lore

I need to assess the delta compression efficiency of various types of binaries. Can I do it this way:

(1) Run git diff between two versions of a binary and pipe the result to a file. (Sample different types of binaries and changes.) (2) Assess the output by size or format or content to determine how well it delta differenced? How would I determine this? What are good absolute delta sizes? What are good delta size ratios compared to total file size? Is the number of hunks in the delta important? (3) Compress the delta file with gzip (or something) and then assess the compression ratio? What is a good compression ratio? What are good delta compressed absolute sizes? What are good delta compressed relative sizes to total file size?

I'm sure I may be missing some things here.  I'm new to assessing delta 
compression efficiency of binaries in general, and specifically for git. 
  Please advise.

v/r, neal

Junio C Hamano· Apr 25, 2012, 21:21 UTC · re: Neal Kreitzinger · lore

Re: how to analyze binary delta compression

Neal Kreitzinger <nkreitzinger@gmail.com> writes:
> I need to assess the delta compression efficiency of various types of
> binaries.  Can I do it this way:
Use test-delta to see how large the output is, perhaps?

← back to recent threads