System Administration Guide Chapter 2, Administering filesystems
Maintaining filesystem efficiency
Three aspects of filesystem usage can degrade the efficiency of filesystems.
Maintaining filesystem efficiency NOTE:
With the exception of limiting directory size,
most of the information that follows
does not apply to HTFS and
DTFS filesystems and is marked accordingly.
Disk fragmentation is the scattering of available disk space
caused by constant use and reuse of filesystem blocks.
``Reducing disk fragmentation''.
Excessively large directories
Directories that contain large numbers of files
(regardless of file size) increase the system search time for files
within the directory.
``Monitoring and limiting directory sizes''.
Empty directory slots
Empty directory slots, caused by large numbers of files being created
and moved or removed from a directory can also cause the directory
to become too large
(EAFS, AFS, and S51K filesystems only).
``Removing empty directory slots''.