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tracking binary files

DISCUSSION bill lam 2 participants 2 messages Jun 15, 2016

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bill lam

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I would like to use git to track some database files of sizes from 1MB to 50MB. I want to know does git compress them for storage or not. If so, what will be the expected compression ratio. Those files normally compressed to 25% of original size using zip.

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Quoted 2 lines · bill lam

I would like to use git to track some database files of sizes from 1MB to 50MB. I want to know does git compress them for storage or not.

Yes, git will compress them via zlib.

Quoted 2 lines

If so, what will be the expected compression ratio. Those files normally compressed to 25% of original size using zip.

Then I would expect the same ratio, since I believe zip and zlib both use the "deflate" algorithm.

Note, however, that git will also do delta compression between versions. So storing N versions of a file should be no _worse_ than zipping and keeping those N versions. But if the database files have small enough changes from version to version (which depends on the database format, and how much the on-disk structure changes for each update) then it will compress even more.

-Peff