> Would there happen to be a SHA1 implementation around that can compute > the SHA1 without first decompressing the data? Databases gain a lot of > speed by using special algorithms that can directly operate on the > compressed data. I can't imagine how. In general, this requires that the compression be carefully designed to be compatible with the algorithms, and SHA1 is specifically designed to depend on every bit of the input in an un-analyzable way. Also, git normally avoids hashing objects that it doesn't need uncompressed for some other reason. git-fsck is a notable exception, but I think the idea of creating special optimized code paths for that interferes with its reliability and robustness goals. -- 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