rsync compression (-z) and timestamp

[Paul Slootman]

On Tue 27 Jan 2009, David de Lama wrote:
> 
> So, I know that with the -z Option rsync compresses the files with gzip, than the files are transfared and at the target machine uncompressed.

No, the data over the wire is compressed with the -z option; not the
file.

> I made a test and transfered a 1GB file. I changed the timestamp with the touch command and rsync needs with the -c Option 42sec and without 80sec!
> I expected it viceversa! How can it be?! (I made the test several times)
> I also changed the user rights with chmod. Here the result were what I expected! Rsync needed 45sec with the -c Option, and 2sec without!

Did you flush your disk cache between each try? At both ends?


Paul