Best way to measure disk bandwidth usage

[Chuck Swiger]

Hi--

On Nov 7, 2007, at 9:41 AM, Andrea Venturoli wrote:
> iostat is also expecially interesting, since it can run non- 
> interactively and I could poll it through cacti...
> However this monitors only raw da devices. Is there a way to get  
> gmirrors monitored?

If they are visible as "drive devices", then yes, iostat can be passed  
a list of devices to monitor instead of the top-level physical devices  
it was showing by default.

> Finally this gives overall MB/s, which is very interesting, but I'd  
> also need to refer this to an end-of-scale value, in order to  
> understand if the disks are working to their fullest (and thus are  
> the bottleneck).
> Is this correct? Where could I desume such a value? (I remember  
> there was an utility... though I don't remember its name).

   diskinfo -vt _device_

...will give you some transfer rate numbers, but note the BUGS section  
of the manpage.  :-)

-- 
-Chuck