Disk Stats

I'm relatively new to Perf Mon and am trying to figure out
the best disk objects to use. I've been watching our
servers and I've noticed that sometimes in the evening the
Avg Disk Q Length goes over acceptable levels. But during
the entire night (or most of it) the Total MBytes/Second
is very high due to backups apparently.
How can I interpret these two numbers? One says the
server is getting slammed all night and the ohter says
it's only having troubles occasionally? Which do I go by?
Dan,
Having high values for Total MBytes/Second is not necessarily bad, all it
indicates is that you're getting good I/O throughput.
However, Avg Disk Queue Length can be a sign of problems, especially when it
gets into the hundreds, because it is indicating that the I/O system cannot
keep up with requests.
For advice on the best SQL Server PerfMon counters for disk I/O, see Tom
Davidson's articles in SQL Magazine.
Hope this helps,
Ron
Ron Talmage
SQL Server MVP
"Dan" <anonymous@.discussions.microsoft.com> wrote in message
news:017601c4a00a$51af0c00$a401280a@.phx.gbl...
> I'm relatively new to Perf Mon and am trying to figure out
> the best disk objects to use. I've been watching our
> servers and I've noticed that sometimes in the evening the
> Avg Disk Q Length goes over acceptable levels. But during
> the entire night (or most of it) the Total MBytes/Second
> is very high due to backups apparently.
> How can I interpret these two numbers? One says the
> server is getting slammed all night and the ohter says
> it's only having troubles occasionally? Which do I go by?