VxFS disk space allocation

Disk space is allocated by the system in 512-byte sectors. An integral number of sectors are grouped together to form a logical block. VxFS supports logical block sizes of 1024, 2048, 4096, and 8192 bytes; the default block size is 1024 bytes for most filesystems. (A larger default may be selected for multi-gigabyte filesystems. The block size can be specified as an argument to the mkfs(ADM) command and can vary between VxFS filesystems mounted on the same system. VxFS allocates disk space to files in extents, which are sets of contiguous blocks.

The VxFS disk structure (Version 4 disk layout) supports up to:

• 2[32] - 1 files

• 2[31] - 1 disk blocks

• 2[40] - 1 bytes (1 terabyte) per file

• sixty-four quadrillion extents per file