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Administration best practices
22 Dell EMC PowerVault ME4 Series and Microsoft Hyper-V | 3921-BP-WS
Some advantages for a many-to-one strategy include the following:
• Fewer ME4 Series array volumes to create and administer (avoids volume sprawl)
• Quicker VM deployment because creating additional guest VMs does not require creation of a new
volume on the ME4 Series array
Some advantages for a one-to-one strategy include the following:
• Easier to isolate and monitor disk I/O patterns for a specific Hyper-V guest VM
• Ability to quickly restore a guest VM by simply recovering the ME4 Series volume from a snapshot
• Gives administrators more granular control over what data gets replicated if ME4 Series volumes are
replicated to another location
• Makes it faster to move a guest VM from one host or cluster to another by remapping the volume
rather than copying large virtual hard disk files from one volume to another over the network
Other strategies include placing all boot virtual hard disks on a common CSV, and data virtual hard disks on
one or more data CSVs.
3.5 Optimize format disk wait time for large volumes
Formatting a large SAN volume mapped to a Windows host (this is not specific to the Hyper-V role) should
complete in a few seconds. If long format wait times are experienced for larger volumes (minutes instead of
seconds), disable the file system Delete Notify attribute on the host by completing the following steps:
1. Access a command prompt on the host server with elevated (administrator) rights.
2. To verify the state of the attribute, type fsutil behavior query disabledeletenotify and press [Enter].
A result of zero means the attribute is enabled.
3. To disable the attribute, type fsutil behavior set disabledeletenotify 1 and press [Enter].
The result should display an attribute value of one. To test the result, map a large temporary volume (several
TB) from the ME4 Series array to the host and format the volume. It should complete in a few seconds.
3.6 Placement of page files
Windows Servers and VMs typically place the page file on the boot volume by default, and automatically
manage page file and memory settings without user intervention. In most cases, these settings should not be
changed, unless, for example, an application vendor provides specific guidance on how to tune the page file
and memory settings to optimize the performance of a specific workload. Ultimately, each customer will need
to decide on the best strategy as they consider variables that are unique to their environment.
With ME4 Series storage, there can be some advantages to placing a page file on a separate volume from
the perspective of the storage array. The following reasons may not be sufficiently advantageous by
themselves to justify changing the defaults, but in cases where a vendor recommends making changes to
optimize a workload, consider the following tips as part of the overall page-file strategy.
• Moving the page file to a separate dedicated volume reduces the amount of data that is changing on
the system (boot) volume. This can help reduce the size of ME4 Series snapshots of boot volumes
which will conserve space in the disk pool.
• Volumes or virtual hard disks dedicated to page files typically do not require snapshot protection, and
therefore do not need to be replicated to a remote site as part of a DR plan. This is especially
beneficial in cases where there is limited bandwidth for replication of volumes and snapshots to
another ME4 Series array.