Re: [rdiff-backup-users] How to speed up rdiff-backup

[Carsten Lorenz]

Steve Clement wrote:

>Carsten Lorenz wrote:
>  
>
>>rdiff-backup needs 132s to transfer a 140MB file (1.1MB/s).
>>While rdiff-backup works on the next file scp transfers the same file in 15s 
>>(9.3MB/s)!
>>    
>>
>What does that mean? scp = 9.3MB/s rdiff-backup = 1.1MB/s
>  
>
If i understand, what you mean, yes :-)
scp transfers this file 9 times faster than rdiff-backup

>>Since we want to backup one tera-byte of data this would last more than a 
>>week.
>>    
>>
>That be bad :)
>  
>
ETA is  Thursday.

>>Has anyone hints how to speedup rdiff-backup?
>>    
>>
>Well if you want to speed up rdiff-backup using ssh/scp as transport you
>might need to look into:
>
>high performance ssh
>
>or if you are copying from a Local "secure" network just use ftp or hell
>why not NFS.
>  
>
We thought about using NFS. Since we use a separate "Network" consisting
of both servers and a cable, it can be configured to be safe.
We will try it, when we create the backup in  the opposite direction.

Since scp and rdiff-backup/ssh both uses ssh2 transferring data, why is
rdiff-backup 9 times slower, while the CPU-usage is low?
I can't see where the bottleneck is.

Thanks, Carsten