Hi,

Les Mikesell wrote on 11.09.2007 um 12:40:21 [Re: [BackupPC-users] files 
already in pool are downloaded]:
> Rich Rauenzahn wrote:
> > 
> >> I don't think the remote rsync passes enough information to match the 
> >> pool hashes.  The check is done against files of the same name/location 
> >> from the last backup and when matches are found there, only file 
> >> differences are transferred.

to the original poster: that is the important part: only files with the same
name (and location, if that is not included in your understanding of "name" :)
are matched, not arbitrary files in the pool. For files in the pool under a
different name, there is *no transfer speedup*, but there *is* the benefit of
not requiring a seperate on-disk (or in-memory) copy on the BackupPC server at
any time including during transfer.

> > I'm looking through the sources now.. I assumed that somehow the 
> > interface to File::RsyncP could return a checksum to BackupPC... can't 
> > tell if they are that tightly bound or not.  How/when does compression 
> > occur?  Ah, I see.  It passes an I/O object into RsyncP.  I think I'll 
> > move this to the devel list =-).

The problem is that BackupPC and rsync use different checksum algorithms.
This has been discussed many times. I believe there is a specialized client
being developped (BackupPCd) which may allow such speedups, but, as Les
says,

> Don't forget that the other end of the conversation is running stock 
> rsync [...]

with stock software it's not possible, and, in my opinion, the ability to
simply use stock software on the client computers is an important feature of
BackupPC.

Regards,
Holger

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2005.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
BackupPC-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/backuppc-users
http://backuppc.sourceforge.net/

Reply via email to