Disk Striping

Disk striping writes data across multiple disk drives instead of just one disk drive. Disk striping involves partitioning each drive storage space into stripes that can vary in size from 2 KB to 128 KB. These stripes are interleaved in a repeated sequential manner. The combined storage space is composed of stripes from each drive. MegaRAID supports stripe sizes of 2 KB, 4 KB, 8 KB, 16 KB, 32 KB, 64 KB, or 128 KB. For example, in a four-disk system using only disk striping (as in RAID level 0), segment 1 is written to disk 1, segment 2 is written to disk 2, and so on. Disk striping enhances performance because multiple drives are accessed simultaneously, but disk striping does not provide data redundancy.

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

Stripe Size The stripe size is the length of the interleaved data segments that MegaRAID writes across multiple drives. MegaRAID supports stripe sizes of 2 KB, 4 KB, 8 KB, 16 KB, 32 KB, 64 KB, or 128 KB.

Chapter 2 Introduction to RAID

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