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MKFS(8) System Manager's Manual MKFS(8) NAME mkfs, mkbitfs, mklost+found - construct a disk file system SYNOPSIS /etc/mkfs special size [ spacing cylsize ] /etc/mkbitfs special size [ spacing cylsize ] /etc/mklost+found DESCRIPTION Mkfs (mkbitfs) constructs a regular (bitmapped) file system on the block device special. Size is the number of 1KB (4KB) blocks on the special file. Values of size for various special files, e.g. ra(4), are given in Section 4. The new file system has a single empty direc- tory and a number of inodes that depends on the size. Spacing and cylsize are used for block allocation. Spacing is the pre- ferred distance between successive blocks of a file; cylsize is the number of blocks the system can use without causing a disk seek. Sub- optimal default values are built into the programs; some reasonable values are suggested below. Mklost+found creates a directory called lost+found in the working di- rectory with several empty slots. This directory is used as a reposi- tory for disconnected files recovered by fsck(8) and chuck(8). EXAMPLES /etc/mkbitfs /dev/ra03 31231 /etc/mount /dev/ra03 /mnt cd /mnt /etc/mklost+found Notice the change of units between ra(4) and here: 31231 = 249848*512/4096. SEE ALSO filsys(5), fsck(8) BUGS Fsck should make lost+found automatically when needed. MACHINE DEPENDENCIES Here are empirically good values for spacing and cylsize for VAX hard- ware. Minor changes, such as a new version of a controller, can inval- idate them. To be certain, run your own experiments. Cylinder size doesn't seem to matter much on RA81 disks. On RA90s, it doesn't matter as long as it is large. Bitmapped (4K) file systems space cyl disk, controller, CPU 2 500 RA90, KDB50, VAX 8550 4 500 RA90, UDA50, VAX 8550 2 40 RA81, KDB50, VAX 8550 3 40 RA81, old KDB50, VAX 8550 3 40 RA81, UDA50, VAX 8550 3 105 Wren VI, Viking UDD, VAX 8550 4 40 RA81, UDA50, VAX-11/750 3 40 RA60, UDA50, VAX-11/750 3 40 RA81, KDA50, MicroVAX II 1 40 RD54, RQDX3, MicroVAX II 3 40 RA81, KDA50, MicroVAX III Old-style (1K) file systems space cyl disk, controller, CPU 5 357 RA81, KDB50, VAX 8550 7 357 RA81, UDA50, VAX-11/780 7 357 RA81, KDA50, MicroVAX II 7 128 RD54, RQDX3, MicroVAX II 6 357 RA81, KDA50, MicroVAX III MKFS(8)