[weinzierl]

Did you make any measurements or back of the envelope calculations what the real world performance impact of this change is.

I don't expect anything horrible, but still curious.

EDIT: After skimming OP I found a few answers.

The message from the The Keccak Team [1] is especially interesting. Summary is that we don't have to worry about performance degradation because of the hash calculation itself. There is a palette of functions which are considered to have a "security level [...] appropriate for your application" and are considerably faster than SHA1.

[1] https://public-inbox.org/git/91a34c5b-7844-3db2-cf29-411df5b...

[hsivonen]

If git changed to BLAKE2b, I'd expect a perf improvement over SHA-1.