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Modifying queue depth and timeouts
17 Dell EMC SC Series: Best Practices with VMware vSphere | 2060-M-BP-V
b. For LSI Logic SAS (LSI_SAS):
Windows Registry Editor Version 5.00
[HKLM\SYSTEM\CurrentControlSet\Services\LSI_SAS\Parameters\Device]
"DriverParameter"="MaximumTargetQueueDepth=128;"
; The semicolon is required at the end of the queue depth value
"MaximumTargetQueueDepth"=dword:00000080
; 80 hex is equal to 128 in decimal
Registry setting for the LSI Logic SAS vSCSI Adapter
c. For VMware Paravirtual SCSI (PVSCSI), the Paravirtual adapter is different from the LSI vSCSI
adapters in that its queue depth can be adjusted higher: Up to 256 for devices and 1024 for the
adapter.
For more information, see the VMware KB article, Large-scale workloads with intensive I/O
patterns might require queue depths significantly greater than Paravirtual SCSI default values.
3. Reboot the virtual machine.
Note: See the VMware Knowledge Base for the most current information about setting the queue depth with
different vSCSI controllers or operating systems.
4.7 Setting operating system disk timeouts
For each operating system, if VMware tools are not installed, the disk timeouts must be set to 60 seconds for
the operating system to handle storage controller failovers properly.
Examples of setting the operating-system timeouts can be found in the section, “Set Timeout on Windows
Guest OS” in the vSphere Storage Guide at VMware vSphere documentation.
The general steps to set the disk timeout within Windows and Linux are listed in the following sections.