On 8 Dec 2007, Johannes Schindelin said: > Hi, > > On Sat, 8 Dec 2007, J.C. Pizarro wrote: > >> On 2007/12/07, "Linus Torvalds" <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: >> >> > SHA1 is almost totally insignificant on x86. It hardly shows up. But >> > we have a good optimized version there. >> >> If SHA1 is slow then why dont he contribute adding Haval160 (3 rounds) >> that it's faster than SHA1? And to optimize still more it with SIMD >> instructions in kernelspace and userland. > > He said SHA-1 is insignificant. Actually davem also said it *is* significant on SPARC. But of course J. C. Pizarro's suggested solution won't work because you can't just go around replacing SHA-1 in git with something else :) you could *add* new hashing methods, but you couldn't avoid SHA-1, and adding a new hashing method would bloat every object and every hash in objects like commits with an indication of which hashing method was in use. (But you know this.) >> 1. "Don't compress this repo but compact this uncompressed repo >> using minimal spanning forest and deltas" ... and then you do a git-gc. Oops, now what? ... or perhaps you want to look something up in the pack. Now you have to unpack a large hunk of the whole damn thing. >> 2. "After, compress this whole repo with LZMA (e.g. 48MiB) from 7zip before >> burning it to DVD for backup reasons or before replicating it to >> internet". > > Patches? ;-) Replicating a pack to the internet is almost invariably replicating *parts* of a pack anyway, which reduces to the problem with option 1 above... -- `The rest is a tale of post and counter-post.' --- Ian Rawlings describes USENET - To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html