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Modifying queue depth and timeouts
14 Dell EMC SC Series: Best Practices with VMware vSphere | 2060-M-BP-V
Example queue utilization with the DSNRO set to 32.
Note: The DSNRO limit does not apply to volumes mapped as raw device mappings (RDMs). Each RDM will
have its own queue.
The DSNRO setting can be modified on a per-datastore basis using the command line:
esxcli storage core device set -d <naa.dev> -O <value of 1-256>
Note: This setting allows fine-tuning of DSNRO on a per-volume basis, however it must be set on each
datastore (and each host) if the queue depth is greater than 32.
To globally set the DSNRO, the easiest method is to use a scripting tool such as the VMware PowerCLI utility.
The following example script demonstrates setting the DSNRO to 64 globally across all datastores, on each
host. Remember that any volume added after this script is ran would need to be changed manually or by
rerunning the script.