Wherever possible it's advisable NOT to run any defragmentation tools on a Nimble Storage platform. The CASL architecture has a built in defrag tool as part of it's garbage collection process (called sweeping) and is an always-on process running in the background of the file system; running a host-side defrag tool will merely change the layout of the blocks within the CASL architecture, leading to potentially worse performance overall.
Thanks for your response, Nick! I just have one clarification on your response: When you said that you shouldn't run a Defrag on a Nimble Storage platform I'm assuming that you mean you shouldn't run Defrag on a Windows Hyper-V Host using the Nimble SAN as a Clustered Shared Volume (CSV). But does your recommendation also include not running a Defrag within the Windows VM's running on the Hyper-V Host? In other words, do you recommend not running Defrag on either the host nor the VM's? Thanks for your help!