Re: how to understand the Q2Q in btt result?

[Ming Zhang <blackmagic02881@gmail.com>]

On Sun, 2007-03-25 at 23:51 -0400, Alan D. Brunelle wrote:
> Ming Zhang wrote:
> > from btt user guide
> >
> > "Q2Q which measures the time between queue traces in the system.
> > This provides some idea as to how quickly IOs are being handed to
> > the block IO layer."
> >
> > does this mean the time between queuing N request and N
> > +1 request?
> >   
> 
> Hi Ming -
> 
> This is the average time between the Q traces being logged. We take the 
> difference between each succeeding Q trace, and divide the sum by the total.

so like block layer idle indicator. maybe a similar D2D will be a nice
device indicator as well.


> 
> Alan
> > thanks!
> >
> > Ming
> >
> >
> > -
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