HP Volume Shadowing for OpenVMS: OpenVMS Version 8.4 > Chapter 10 Performance Information for Volume Shadowing

Striping (RAID) Implementation

HP RAID Software for OpenVMS provides ways to configure and use disk drives so that they achieve improved I/O performance. RAID (redundant arrays of independent disks) uses striping technology to chunk data and distribute it across multiple drives. RAID software is available in various levels, one of which is volume shadowing. Table 10-1 describes RAID levels.

Table 10-1 RAID Levels

RAID Level Description

Level 0

Striping with no redundancy.

Level 1

Shadowing.

Levels 0 + 1

Striping and shadowing together.

Level 3

Striped data with dedicated parity drive. Drives are rotationally synchronized.

Level 5

Striped data and parity.

Level 6

Striped data and parity with two parity drives.

 

Shadowing striped drives can increase both performance and availability, because you can achieve faster response time with striping and data redundancy with shadowing. In addition to shadowing striped sets, you can also stripe shadow sets. Each strategy offers different advantages and tradeoffs in terms of availability, performance, and cost.