Dell PowerVault MD3200 CLI Guide - Page 98

request leaves other disks available to simultaneously service other requests. If the virtual disk is in a single-user large I/O environment, performance is maximized when a single I/O request is serviced with a single data stripe; use smaller values for the segment size. To change the segment size, run the following command: set virtualDisk ([virtualDiskName] | ) segmentSize=segmentSizeValue where, segmentSizeValue is the new segment size you want to set. Valid segment size values are 8, 16, 32, 64, 128, 256, and 512. You can identify the virtual disk by name or World Wide Identifier (WWID) (see "Set Virtual Disk" on page 218). Defragmenting a Disk Group When you defragment a disk group, you consolidate the free capacity in the disk group into one contiguous area. Defragmentation does not change the way in which the data is stored on the virtual disks. As an example, consider a disk group with five virtual disks. If you delete virtual disks 1 and 3, your disk group is configured in the following manner: space, virtual disk 2, space, virtual disk 4, virtual disk 5, original unused space When you defragment this group, the space (free capacity) is consolidated into one contiguous location after the virtual disks. After being defragmented, the disk group is: virtual disk 2, virtual disk 4, virtual disk 5, consolidated unused space To defragment a disk group, run the following command: start diskGroup [diskGroupNumber] defragment where, diskGroupNumber is the identifier for the disk group. NOTE: Defragmenting a disk group starts a long-running operation. 98 Maintaining a Storage Array