MASFG - give mass storage space summary.

Syntax:

MASFG [devname|option]*

Options:

(+|-)Headings (-)        (+|-)Nofms (+)
(+|-)Perm (+)            (+|-)ReMoveable (+)
(+|-)RawDump (-)         (+|-)Summary (+)
(+|-)Verbose

devname: names a device for which statistics should be listed. If several devices are specified, stats will be given for all of them. References to non-existent devices are ignored. If no devname is supplied, all devices on the system will be listed.
+Headings: print a title and heading line.
-Nofms: does not list devices on which no permanent files are kept.
-Perm: does not list permanently mounted packs on which permfiles may be kept.
-ReMoveable: does not list removeable devices.
+RawDump: gives a list of all the holes and their sizes for each device.
-Summary: gives the listing without summary lines.
+Verbose: implies +Headings and +Summary.
-Verbose: implies -Perm, -Nofms, -ReMoveable, and -Headings, giving only the summary.

Description:

MASFG is used to supply a summary of the space statistics of mass storage devices configured on the system.

The "+Perm", "+Nofms" and "+ReMoveable" options are or'ed together and and'ed with the named devices, if any.

The columns of output have the following meanings.

dvc (device): device name (primary one in system name table)
type: device configuration: perm space, temp space, or removeable pack
au: llinks per allocation unit
max: maximum number of llinks on device
scr: scratch number of llinks (llinks not assigned for perm files)
avl: number of llinks left on device currently (scr-avl = temp space allocated on this device)
ovf: amount of space which has overflowed past the end of the AST
catspc: available space for catalog llinks
holes: number of holes (unallocated areas) on the pack
lrg: number of llinks in the largest hole
def: number of defective llinks on device
%full: per cent of the AST in use
name: name of pack mounted on that device

Most of these statistics are obtained from the Available Space Table (AST) for the device, which contains a map of the unused space in a slightly bizarre format. The size of the used area of AST depends not only on the number of holes, but also on their size and distribution. A device which is either all in use or all free will tend to have an AST about 27% full on our system.

If the filespace on a device becomes so fragmented that there is no room in the AST to list all the holes, then the AST has "overflowed". The llinks above the highest seek-address hole in the AST cannot be accounted for and are listed in the "overflow" column.

Should the filespace become less fragmented after an AST has overflowed, the unaccountable space will not be re-claimed until the next system boot.