Re: [rdiff-backup-users] [PATCH] Optimization for --check-destination

[Andrew Ferguson]

On Jun 25, 2008, at 10:24 AM, Josh Nisly wrote:

> Actually, since the optimization affects determining whether the  
> destination needs checking, it speeds up all backups.
>
> What is happening is that we are going through the rdiff-backup-data  
> directory, looking for current_mirror files. But for each file in  
> the directory, we instantiate an RORPath object, which goes to the  
> server to set file information. The problem is that it doesn't need  
> any file information, since it works on the filename alone.
>
> Since this involves the rdiff-backup-data directory, the size of the  
> repository is irrelevant; it's the number of times it has been  
> backed up that matters, and it is a linear slowdown.
>
> What this patch does is factor out the logic of determining based on  
> a filename whether a file is an increment or not, thus removing the  
> need to go to the remote end for every file. It does go to the  
> remote end for each file that matches, but there are only one or two  
> matches most of the time.



Smart move, Josh. I have added the patch to CVS.


thanks,
Andrew