[Box Backup] BlockSize and large file diffs

[Ben Summers]

On 15 Nov 2005, at 17:01, Gary wrote:

> Hi,
>
> Question: is there anyone out there who experimented with
> raidfile.config, BlockSize, and large file uploads? I currently have
> the following raidfile.config:
>
> disc0
> {
>         SetNumber = 0
>         BlockSize = 10240
>         Dir0 = /var/bbstored
>         Dir1 = /var/bbstored
>         Dir2 = /var/bbstored
> }
>
> ... with the block size of 10240 (10k, I'm ok with storage  
> inefficiency
> of partially used blocks). I backup quite a few files ranging from
> 500MB to 2GB. Any idea whether this setting (or any other) affects the
> efficiency of the diffing algorithm, or the size of download of block
> lists for file diffs, in the original version of BoxBackup and/or  
> Jon's
> improved algorithm?
>
> It would be cool if I could create a script that would go over a  
> backup
> set, run some math calculations, and perhaps recommend a set of backup
> settings (BlockSize, DiffingUploadSizeThreshold, etc.)


Your script would find that this makes absolutely no difference.  
These settings affect storage on the server only. Diffing is done on  
the client.

Ben