	ramfs - An automatically resizing memory based filesystem


  Ramfs is a file system which keeps all files in RAM. It allows read
  and write access. In contrast to RAM disks, which get allocated a
  fixed amount of RAM, ramfs grows and shrinks to accommodate the
  files it contains.

  You can mount the ramfs with:
      mount -t ramfs none /mnt/wherever

  Then just create and use files. When the filesystem is unmounted, all
  its contents are lost.

  NOTE! This filesystem is probably most useful not as a real
  filesystem, but as an example of how virtual filesystems can be
  written.

Resource limits:

By default a ramfs will be limited to using half of (physical) memory
for storing file contents, a bit over that when the metadata is
included. The resource usage limits of ramfs can be controlled with
the following mount options:

	maxsize=NNN
		Sets the maximum allowed memory usage of the
filesystem to NNN kilobytes. This will be rounded down to a multiple
of the page size. The default is half of physical memory. NB.  unlike
most of the other limits, setting this to zero does *not* mean no
limit, but will actually limit the size of the filesystem data to zero
pages. There might be a use for this in some perverse situation.
	
	maxfilesize=NNN
		Sets the maximum size of a single file on the
filesystem to NNN kilobytes. This will be rounded down to a multiple
of the page size. If NNN=0 there is no limit. The default is no limit.

       maxdentries=NNN
		Sets the maximum number of directory entries (hard
links) on the filesystem to NNN. If NNN=0 there is no limit. By
default this is set to maxsize/4.

	maxinodes=NNN
		Sets the maximum number of inodes (i.e. distinct
files) on the filesystem to NNN. If NNN=0 there is no limit. The
default is no limit (but there can never be more inodes than dentries).
