3PAR InForm® OS 2.2.4 Concepts Guide (320-200085 Rev B, March 2009)

InForm OS Version 2.2.4 3PAR InForm OS Concepts Guide
11.1
Physical Disks
11
Physical Disks
In this chapter
11.1 Physical Disk Chunklets 11.1
11.2 Physical Disk Locations 11.2
11.1 Physical Disk Chunklets
Physical disks are divided into chunklets, where each chunklet occupies 256 MB of contiguous
space.
Space on a physical disk is allocated as follows:
■ One chunklet is reserved for the table of contents (TOC), which contains the internal
description of the system. The TOCs on all physical disks in the system contain the same
information.
■ 4 MB are reserved for diagnostic use--2 MB beginning after the TOC and 2 MB from the
end of the disk logical-block address.
■ One or more chunklets are allocated as spares. These spare chunklets are used to hold
relocated data during disk failures and during maintenance procedures. Spares are created
NOTE: See Appendix B, Servicing Hardware and Moving Hosts, for information on
servicing physical disks.