Solved

disk queue length

Posted on 2013-01-19
4
539 Views
Last Modified: 2013-02-07
i have a hp raid 10 array with 6 disks, what is the threshold for disk queue length? is it 2 per disk? so in my case it would 12?
0
Comment
Question by:Kylo Ren
  • 2
4 Comments
 
LVL 11

Assisted Solution

by:gmbaxter
gmbaxter earned 250 total points
ID: 38797171
If the average disk queue length is greater than twice the number of disks in the volume/array then the storage is the bottleneck, so in your case yes 12.

You could certainly look into the average read and average write indications separately to get further information.
0
 
LVL 79

Expert Comment

by:David Johnson, CD, MVP
ID: 38797217
@gmbaxter: Yes that is the theory.. Whether or not it affects the user experience is another question. On my drive E (6 Drives in a Storage Space) the current disk queue is 58 (I am pausing a Vmware workstation), yet it doesn't impact my other running applications..
0
 
LVL 11

Expert Comment

by:gmbaxter
ID: 38797986
Yes it does depend on the application in that respect. In a 16 disk array running user home folders I've seen queues of 35 severely affecting performance.

The main thing to do is to analyse the issue, if you view the application as a user at peak times and you think there is a problem, then look into where the problem originates from. If however things are running smoothly, then don't just throw money at a san/array just because a graph says so.
0
 
LVL 2

Accepted Solution

by:
MaxEL_UA earned 250 total points
ID: 38804396
Here is a TechNet article for bottleneck calculations
http://technet.microsoft.com/en-us/library/dd723635%28v=office.12%29.aspx
0

Featured Post

Best Practices: Disaster Recovery Testing

Besides backup, any IT division should have a disaster recovery plan. You will find a few tips below relating to the development of such a plan and to what issues one should pay special attention in the course of backup planning.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Recently, I was assigned the task of performing a hardware refresh in the datacenter. The previous Windows 2008 systems were connected to the SAN via fiber channel HBA’s and among other thing, had PowerPath installed in order to provide sufficient f…
This article will review the basic installation and configuration for Windows Software Update Services (WSUS) in a Windows 2012 R2 environment.  WSUS is a Microsoft tool that allows administrators to manage and control updates to be approved and ins…
In this Micro Tutorial viewers will learn how they can get their files copied out from their unbootable system without need to use recovery services. As an example non-bootable Windows 2012R2 installation is used which has boot problems.
This tutorial will walk an individual through the process of configuring their Windows Server 2012 domain controller to synchronize its time with a trusted, external resource. Use Google, Bing, or other preferred search engine to locate trusted NTP …

773 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question