NAME    [Toc]    [Back]

     memcontrol -- control system cache behaviour with respect to memory

SYNOPSIS    [Toc]    [Back]

     memcontrol list [-a]
     memcontrol set -b base -l length -o owner attribute
     memcontrol clear -o owner
     memcontrol clear -b base -l length

DESCRIPTION    [Toc]    [Back]

     A number of supported system architectures allow the behaviour of the CPU
     cache to be programmed to behave differently depending on the region
     being written.

     The memcontrol utility provides an interface to this facility, allowing
     CPU cache behavior to be altered for ranges of system physical memory.

     These ranges are typically power-of-2 aligned and sized, however the specific
 rules governing their layout vary between architectures.  The
     memcontrol utility does not attempt to enforce these rules, however the
     system will reject any attempt to set an illegal combination.

     list   List range slots.

	    -a	    List all range slots, even those that are inactive.

     set    Set memory range attributes.

	    -b base
		    Memory range base address.

	    -l length
		    Length of memory range in bytes, power of 2.

	    -o owner
		    Text identifier for this setting (7 char max).

	    attribute
		    Attributes applied to this range; combinations of force,
		    uncacheable, write-combine, write-through, write-back, and
		    write-protect.

     clear  Clear memory range attributes.  Ranges may be cleared by owner or
	    by base/length combination.

	    To clear based on ownership:

	    -o owner
		    All ranges with this owner will be cleared.

	    To clear based on the base/length combination:

	    -b base
		    Memory range base address.

	    -l length
		    Length of memory range in bytes, power of 2.

	    Base and length must exactly match an existing range.

SEE ALSO    [Toc]    [Back]

     mem(4)


FreeBSD 5.2.1		      September 15, 2002		 FreeBSD 5.2.1