HP 3PAR Windows 2012 and Windows Server 2008 Implementation Guide

Removing a Storage Volume from the Host
To remove a volume from the Windows Server 2012/2008 host, follow standard Microsoft
administrative procedures for removing a volume, and follow the HP 3PAR StoreServ Storage
standard procedure to remove a volume.
NOTE: Removing a disk from a Windows Server 2012/2008 host does not erase the data on
the disk. If there is concern about the data on the disk, you might want to use a third party utility
that erases the data on the disk before you remove it from the Windows Server 2012/2008 host.
SCSI UNMAP Primitive Support for Windows Server 2012
HP 3PAR OS 3.1.1 introduced support for the UNMAP storage primitive (operation code 42h)
which is supported by Windows Server 2012 and 2012 R2 with the NTFS filesystem. UNMAP
causes the HP 3PAR StoreServ Storage to reclaim storage space on a thinly-provisioned virtual
volume (TPVV) when data or files are deleted on a supported filesystem type. This feature is useful
in maintaining the volume as a thin volume with no storage disk space allocated for files that are
deleted.
NOTE: Currently, the Windows Server 2012 and 2012 R2 Resilient File System (ReFS) does not
take advantage of space reclaimed from files deleted by using the UNMAP primitive on
thinly-provisioned LUNs.
Offloaded Data Transfer (ODX) Support for Windows Server 2012
HP 3PAR OS 3.1.2 introduces support for offloaded data transfer (ODX), which is supported by
Windows Server 2012 and 2012 R2 with the NTFS filesystem.
In a traditional file transfer/copy operation between two LUNs on the same storage array,
buffered-read and buffered-write operations would be used on the host to complete the request.
With arrays that support ODX, Windows Server 2012 and 2012 R2 can complete the request by
offloading the file transfer to the storage array. By doing so, ODX minimizes latencies, maximizes
array throughput, and reduces resource usage such as CPU and network consumption on the host
computer. Windows Server 2012 offloads file transfers transparently and automatically when you
move or copy files, regardless of whether you drag-and-drop files through File Explorer or use the
command-line file copy commands. For more information about ODX, see the following website:
Microsoft
Removing a Storage Volume from the Host 67