System.IO.DiskQueue and System.IO.DiskTime

[kghammond]

As you can tell, I am slowly making my way through all the agent paramaters.  Most of our servers have seperate OS and DATA disk sub-systems.

I assume System.IO.DiskQueue and System.IO.DiskTime are averaged totals for all disk subsystems on the server.  Is that correct?

If the OS is and the DATA volume is   Would the following counters more accurately reflect the current state of the disk queue length and the disk time for each volume?

Counter = System.IO.DiskQueue.C:"\LogicalDisk(C:)\Current Disk Queue Length":60:A:INT:"Average Current Disk Queue Length on C:"
Coutner = System.IO.DiskTime.C:"\LogicalDisk(C:)\% Disk Time":60:A:INT:"Average % Disk Time on C:"
Counter = System.IO.DiskQueue.D:"\LogicalDisk(D:)\Current Disk Queue Length":60:A:INT:"Average Current Disk Queue Length on D:"
Coutner = System.IO.DiskTime.D:"\LogicalDisk(D:)\% Disk Time":60:A:INT:"Average % Disk Time on D:"

Thank You,
Kevin

[victor]

Yes, then you will get more detailed picture. From my experience, I often configure only common System.IO.DiskQueue parameter on all servers, and then add per disk queue/time for those servers where I see need for more detailed information.

Best regards,
Victor

[kghammond]

Can you explain the System.IO.DiskTime paramater?

I assumed this was a % cpu for all disk activity on the server.  It seems this is a total time counter in ms maybe?  Is this assumption correct?  How do you use this information?

Is there any way to relate this to % cpu?

Thank you,
Kevin

[victor]

Hello!

It's just a built-in alias for \PhysicalDisk(_Total)\% Disk Time performance counter. It is the percentage of elapsed time that all disk drives were busy servicing read or write requests. It can be used to measure physical disk load, but it is not related to % of CPU time spent on I/O.

Best regards,
Victor

[kghammond]

Thank you,

I will try to get a better understanding of that counter.  On one of our servers, we are seeing regular valures around 200 - 250 for that paramater and spikes over 600.

Thanks again,
Kevin