mount_memfs.1m (2010 09)

mount_memfs(1M) mount_memfs(1M)

Notes

Quotas are not available for MemFS ﬁle systems.

ACLs are not available for MemFS ﬁle systems.

MemFS ﬁle systems are largeﬁles-enabled.

MemFS ﬁle systems do not support forced unmount.

MemFS ﬁle systems cannot be mounted read only.

DIAGNOSTICS

umount complains if the directory is not mounted or if it is busy. The ﬁle system is busy if it contains an

open ﬁle or some logged-in user’s working directory.

EXAMPLES

Mount a MemFS of size 100 MB on

/mnt:

mount -F memfs -o size=100MB /mnt

Mount a MemFS of size 100 MB with ﬁle limit to 500, root permissions to 0777, owner as user ID 20 and

group as group ID 40 on /mnt:

mount -F memfs -o size=100MB,ninode=500,mode=0777,user=20,group=40

/mnt

Unmount a local MemFS ﬁle system:

umount /mnt

WARNINGS

Swap space is reserved when writing data on to MemFS ﬁle systems. Data will be swapped out when

there is memory pressure. Excessive usage of swap space by writing large sized ﬁles on to MemFS ﬁle

systems will reduce the swap space available for others. This reduced swap space can lead the system to

an unstable or unresponsive state. Similarly, applications which use more swap space will reduce the

swap space available for MemFS. This situation leads to running out of space on MemFS ﬁle systems.

HP recommends having swap space be more than the cumulative size of the MemFS ﬁle systems. Use the

size option to deﬁne a ﬁle system size that is equal to or smaller than the swap space. See swapon(1M)

for information about deﬁning swap space.

AUTHOR

mount was developed by HP, AT&T, the University of California, Berkeley, and Sun Microsystems.

FILES

/etc/fstab Static information about the ﬁle systems

/etc/mnttab Mounted ﬁle system table

/etc/passwd

/etc/group