mount_xmemfs(1M)					  System Administration Commands					  mount_xmemfs(1M)

NAME

       mount_xmemfs - mount xmemfs file systems

SYNOPSIS

       mount -F  xmemfs [generic_options] -o[largebsize,]size=sz [-O] special mount_point

DESCRIPTION

       xmemfs  is  an extended memory file system which provides file system semantics to manage and access large amounts of physical memory which
       can exceed 4 GB in size.

       mount attaches a xmemfs file system to the file system hierarchy at the	pathname  location  mount_point,  which  must  already	exist.	If
       mount_point  has  any  contents	prior  to  the	mount  operation,  these  remain hidden until the file system is once again unmounted. The
       attributes (mode, owner, and group) of the root of the xmemfs filesystem are inherited from  the   underlying  mount_point,  provided  that
       those attributes are determinable.  If not, the root's attributes are set to their default values.

	The special argument is not currently used by xmemfs but a placeholder, (such as xmem), needs to be specified nevertheless.

OPTIONS

       See mount(1M) for the list of supported generic_options.

       -ospecific_options      Specify	xmemfs	file  system  specific	options  in  a comma-separated list with no intervening spaces. If invalid
			       options are specified, a warning message is printed and the invalid options are ignored.

			       The size=sz specific option is required.

			       The following options are available:

			       size=sz	       The sz argument specifies the desired size of this particular xmemfs file system. If the  sz  argu-
					       ment  has  a  k	suffix,  the  number  is  interpreted  as kilobytes. An m suffix is interpreted as
					       megabytes and g is interpreted as gigabytes. A sz specified with no suffix is interpreted as bytes.

					       In all cases, the actual size of the file system is the number of bytes specified,  rounded  up	to
					       the physical pagesize of the system or to the large page size if largebsize is specified.

					       This specific_option is required.

			       largebsize      If  largebsize  is specified, xmemfs uses the large memory page size as the file system block size.
					       On IA32, the large memory page size with mmu36 which supports PAE (Physical Address Extension) is 2
					       MB.  The  large	memory page size without mmu36/PAE is 4 MB. If there is no large page support, the
					       file system block size is PAGESIZE.

       -O		       Overlay mount. Allow the file system to be mounted over an existing mount point, making the underlying file  system
			       inaccessible.   If  a  mount is attempted on a pre-existing mount point without setting this flag, the mount fails,
			       producing the error device busy.

FILES

       /etc/mnttab		       table of mounted file systems

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |ATTRIBUTE TYPE		     |ATTRIBUTE VALUE		   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+
       |Architecture		     |i386			   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       mount(1M), mount(2), mkdir(2), open(2), umount(2), mnttab(4), attributes(5),xmemfs(7FS)

NOTES

       If the directory on which a file system is to be mounted is a symbolic link, the file system is mounted on the directory to which the  sym-
       bolic link refers, rather than on top of the symbolic  link itself.

       The only file types allowed on xmemfs are directories and regular files. The execution of object files resident in xmemfs is not supported.
       Execution is prevented by not allowing users to set execute permissions on regular files.

SunOS 5.10							    27 May 1999 						  mount_xmemfs(1M)