[Box Backup] local backups really slow

[Martin Ebourne]

On Tue, 2006-09-26 at 23:04 -0400, rs@boxbackup.spam.futz.org wrote:
> Hi,
> 
> I'm trying to backup to a server running on the local machine to set up a disk
> I'm going to use at a remote site. I figured a local backup would be much
> faster than having to back up 40G of data over the net. However, it's not
> nearly as fast as I expected. It seems to only be going at about 200K/s, which
> is paltry in comparison to the M/s rates I see when doing local rsyncs. The
> src and destination drives are on different IDE busses.
> 
> Does that seem really slow to those of you using box backup, maybe over a
> local lan? Might have have some real simple setting wrong? It's not a slow
> machine - Athalon 2G, with 2.5G of memory.. CPU usage (per top) is running
> about 10% user and 88% wait, and has been for several hours. The client/server
> addresses are on the loopback interface.
> 
> Any ideas on why it's so slow, or how I could speed it up?

The machine is heavily IO bound and it's clearly not transfer rate so it
is presumably seeking that is giving the trouble.

Given that rsync doesn't have this problem maybe it's the seeking on the
server side. Would be worth confirming which disk is causing the
trouble. Have a go with iostat see what you can come up with.

Cheers,

Martin.