Dell MD3600I, MD3620I Segment Size, Virtual Disk Operations, Virtual Disk Initialization

actual storage. RAID 10 is automatically used when a RAID level of 1 is chosen with four or more physical disks. RAID 10 works well for medium- sized databases or any environment that requires high performance and fault tolerance and moderate-to-medium capacity.

Segment Size

Disk striping enables data to be written across multiple physical disks. Disk striping enhances performance because striped disks are accessed simultaneously.

The segment size or stripe element size specifies the size of data in a stripe written to a single disk. The storage array supports stripe element sizes of 8, 16, 32, 64, 128, 256, and 512 KBs. The default stripe element size is 128 KB.

Stripe width, or depth, refers to the number of disks involved in an array where striping is implemented. For example, a four-disk group with disk striping has a stripe width of four.

NOTE: Although disk striping delivers excellent performance, striping alone does not provide data redundancy.

Virtual Disk Operations

Virtual Disk Initialization

Every virtual disk must be initialized. Initialization can be done in the foreground or the background. A maximum of four virtual disks can be initialized concurrently on each RAID controller module.

Background Initialization

The storage array executes a background initialization when the virtual disk is created to establish parity, while allowing full host server access to the virtual disks. Background initialization does not run on RAID 0 virtual disks. The background initialization rate is controlled by MDSM. To change the rate of background initialization, you must stop any existing background initialization. The rate change is implemented when the background initialization restarts automatically.

Planning: MD3600i Series Storage Array Terms and Concepts

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