Interaction of compressed files and other commands

Table: describes how compressed files interact with other Storage Foundation commands and base operating system commands.

Table:

Command

Interaction with compressed files

df

The df command shows the actual blocks in use by the file system. This number includes the compression savings, but the command does not display the savings explicitly.

See the df(1) manual page.

du

The du command usually uses the block count and thus implicitly shows the results of compression, but the GNU du command has an option to use the file size instead, which is not changed by compression.

See the du(1) manual page.

fsadm -S

The fsadm -S compressed command reports the space savings due to compressed files.

See the fsadm_vxfs(1) manual page.

fsmap -p

The fsmap command can report information on compressed and uncompressed extents with the -p option. The reported logical size is the size of the uncompressed data, while the reported extent size is the size of the compressed data on disk. For compressed extents, the two sizes might differ.

See the fsmap(1) manual page.

ls -l

ls -s

The inode size reported by a stat call is the logical size, as shown by the ls -l command. This size is not affected by compression. On the other hand, the block count reflects the actual blocks used. As such, the ls -s command shows the result of compression.

See the ls(1) manual page.

vxdump

The vxdump command uncompresses compressed extents as it encounters them, meaning that compression is not preserved across a backup or restore operation.

vxquota

Your quota usage decreases based on the space saved due to compression.

See the vxquota(1M) manual page.