rdiff-backup across the network

[Tan, Stephen]

Hi, I'm considering using rdiff-backup here at work and I'm generally vry
impressed with the concept and ease of use of this script! 

It has a very low cpu and memory overhead which is welcome.

There is one thing I was wondering about though, and that is the speed
across the network of rdiff-backup. I am running across a 100mbit switched
LAN, and using rsync, I can acheive a transfer rate of about 1.5 mb/s
(albeit with the CPU consumption going very high.) 

I get about about 4-5 mb/min (for actual data transfer speed) using
rdiff-backup.

You did mention that rdiff-backup was slower than rsync, but I did
anticipate such a large factor.

Is this because: 

(i) increasing throughput would load the cpu more? 
(ii) ssh is a bottleneck? (I think this is unlikely!)
(iii) the rdiff algorithm is set for smaller bandwidths?

I'd love to be able to increase the throughput by a factor of 2-3 if
possible - I have some cpu on both ends to spare and lots of bandwidth. Is
this possible?

many thanks

Stephen Tan (Sega Europe sysadmin)