rsync'ing large files

Wayne Davison wayned at
Thu Apr 22 17:47:00 GMT 2004

On Thu, Apr 22, 2004 at 11:23:18AM -0400, Brian Cuttler wrote:
> I can't address the algoritm questions but I'll tell you that we
> had a tremendous improvement is speed when we switched to a newer
> version of rsync.

Yes, rsync 2.6.0 has some big improvements in the checksum processing
for large files (which makes them transfer with fewer chances for
mismatched blocks):

    * Per-file dynamic block size is now sqrt(file length).  The
      per-file checksum size is determined according to an algorithm
      provided by Donovan Baarda which reduces the probability of rsync
      algorithm corrupting data and falling back using the whole md4
      checksums. (J.W. Schultz, Donovan Baarda)


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