What's best and easiest to check sync result ?

[Smoot Carl-Mitchell]

On Tue, 2008-06-10 at 10:33 -0400, Bart Silverstrim wrote:

> But when I did it to copy files as backups from my hard disk to an 
> external drive, it would copy the whole file; so if I have a 5 gig 
> tarfile, it copies the 5 gig over.
> 
> I thought from the docs that if the 5 gig file was something that just 
> had a portion altered, like a 10 meg chunk, that 10 meg would get copied 
> over to the appropriate section of the destination 5 gig file. But no, 5 
> gig gets copied because it had a difference.

The default for local copies is "whole files" (the -W  or --whole-file
option).  You can turn this off for local copies by specifying the
--no-W option.  See the man page for details.

It should be pointed out that running the differential algorithm locally
may in fact take longer than just copying the whole file.  I'd
experiment with your specific situation to see if there is any advantage
one way or the other.

Any easy test is to "touch" your source file and then run rsync with the
--no-whole-file switch. e.g

touch source
rsync --no-while-file source destination
-- 
Smoot Carl-Mitchell
System/Network Architect
smoot at tic.com
+1 480 922 7313
cell: +1 602 421 9005