IBM 000-8697 Manual Do Utilizador

System Architecture

The ninth reserved page in the root dbspace is

PAGE_1MCHUNK.

 The tenth

reserved page,

PAGE_2MCHUNK

, is the second page in the pair.

The tbinit daemon uses the mirror chunk page to describe each mirror
chunk, its pathname, its relation to the dbspace, and its current status.

Below listed the mirror chunk fields and definitions. To obtain a listing of the
reserved page, execute the command tbcheck -pr.

Chunk flags:

0x01
0x02
0x04
0x08
0x20
0x40
0x80
0x100
0x200
0x400

Raw device
Block device
UNIX file
Needs sync() to operating system
Chunk is offline
Chunk is online
Chunk is in recovery
Chunk is newly mirrored
Chunk is part of a blobspace
Chunk is being dropped

Chunk name length

Length of the chunk pathname

Chunk path

Operating system path for chunk

Primary chunk number

Chunk number

Next chunk in dbspace

Number of the next chunk in the dbspace

Chunk offset

Offset of chunk, in pages

Chunk size

Number of pages in the chunk

Number of free pages

Number of free pages in the chunk

Dbspace number

Number of this chunk’s dbspace

 (1 of 2)

 (2 of 2)