American Megatrends MegaRAID Express 500, Руководство по оборудованию

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Chapter 2 Introduction to RAID
9
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 Express 500 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 a measure of 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
Express 500 writes across multiple drives. MegaRAID Express 500 supports
stripe sizes of 2 KB, 4 KB, 8 KB, 16 KB, 32 KB, 64 KB, or 128 KB.