jw at pegasys.ws
Fri May 16 10:11:31 EST 2003
On Thu, May 15, 2003 at 04:51:36PM +0200, Paul Slootman wrote:
> >From the manpage:
> By default the primary checksum used in rsync is a very strong
> 16 byte MD4 checksum. In most cases you will find that a trun-
> cated version of this checksum is quite efficient, and this will
> decrease the size of the checksum data sent over the link, mak-
> ing things faster.
> You can choose the number of bytes in the truncated checksum
> using the --csum-length option. Any value less than or equal to
> 16 is valid.
> Note that if you use this option then you run the risk of ending
> up with an incorrect target file. The risk with a value of 16 is
> microscopic and can be safely ignored (the universe will proba-
> bly end before it fails) but with smaller values the risk is
> Current versions of rsync actually use an adaptive algorithm for
> the checksum length by default, using a 16 byte file checksum to
> determine if a 2nd pass is required with a longer block check-
> sum. Only use this option if you have read the source code and
> know what you are doing.
> Of course, if you've read the source code, you'd know that there's no
> such option :-) So, I request that this be removed from the manpage.
If you were looking at CVS you'd know it already has.
J.W. Schultz Pegasystems Technologies
email address: jw at pegasys.ws
Remember Cernan and Schmitt
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