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E-12 understanding drive arrays, Data, Data daz-9-11.eps – Compaq 3200 User Manual

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E-12 Understanding Drive Arrays

Writer: Rickard Project: Compaq Smart Array 3200 Controller Reference Guide Comments: 340862-002

File Name: L-APPE.DOC Last Saved On: 12/7/98 9:30 AM

COMPAQ CONFIDENTIAL - NEED TO KNOW REQUIRED

For example, consider an operating system that typically requests data in
32-sector blocks (a sector contains 512 bytes of data). The Smart Array 3200
Controller distributes the data so that the first 32 sectors of data are on the first
drive in the array. The Smart Array 3200 Controller continues distributing the
next 32 sectors on the second drive, the next 32 sectors on the third drive, and so
on. Evenly distributed user data across all drives in an array results in improved
performance by allowing data access to all drives simultaneously.

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Figure E-8. Data striping distributes data across all physical drives