Re: Disk Stats

From: Ron Talmage (rtalmage_at_prospice.com)
Date: 09/22/04 

Date: Tue, 21 Sep 2004 22:43:50 -0700

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?