SQL VM上磁盘延迟高, 但Host和Storage Array上的延迟却很低的问题

按照下面的步骤, 问题解决.

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Per Microsoft DDK, Microsoft storport.sys maintains a device queue for each device it controls and the storport interface allows the underlying miniport to set the maximum queue depth of the device queue.

The maximum queue depth value, as was told by Microsoft port driver developer, is 254. Qlogic sets the default value to 32.

Please note that the Microsoft storport.sys driver has total control of the queue depth of the device queue, qlogic miniport merely sets the value using the predefined storport interface call and procedure as informed by Microsoft.

 

Please use the following procedure to change the qd parameter:

• 1. Click on "Start", select "Run", and open the REGEDIT/REGEDT32 program.
• 2. Select HKEY_LOCAL_MACHINE and follow the tree structure down to the QLogic driver as follows:

        HKEY_LOCAL_MACHINE

              SYSTEM

                  CurrentControlSet

                          Services

                                 Ql2300

                                         Parameters

                                               Device

• 3. Double click on DriverParameter:REG_SZ:qd=32
• 4. If the string "qd=" does not exist, append to end of string ;qd=32
• 5. Enter a value upto 254 (0xFE). The default value is 32 (0x20). (这里我设置的是64.)
• 6. Click OK.
• 7. Exit the Registry Editor, then shutdown and reboot the system.

 

Articles helped fix this issue

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http://social.technet.microsoft.com/Forums/windowsserver/en-US/d4a49b4d-fe8f-4470-8353-33ee5beb9551/how-to-check-qlogic-hba-adapter-queue-depth-in-windows-2008-r2?forum=winservergen

 

Why this would work

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Troubleshooting Storage Performance in vSphere – Storage Queues

https://blogs.vmware.com/vsphere/2012/07/troubleshooting-storage-performance-in-vsphere-part-5-storage-queues.html

SQL Server and HBA Queue Depth Mashup

http://blogs.msdn.com/b/joesack/archive/2009/01/28/sql-server-and-hba-queue-depth-mashup.aspx

 

Further reading

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Troubleshooting Storage Performance in vSphere – Part 1 – The Basics

http://blogs.vmware.com/vsphere/2012/05/troubleshooting-storage-performance-in-vsphere-part-1-the-basics-.html

Troubleshooting Storage Performance in vSphere – Part 2
http://blogs.vmware.com/vsphere/2012/06/troubleshooting-storage-performance-in-vsphere-part-2.html

Troubleshooting Storage Performance in vSphere (Part 3) – SSD Performance
http://blogs.vmware.com/vsphere/2012/06/troubleshooting-storage-performance-in-vsphere-part-3-ssd-performance.html