NAME
memconfig —
control system cache behaviour with
respect to memory
SYNOPSIS
memconfig |
list [-a] |
memconfig |
set -b
base -l
length -o
owner attribute |
memconfig |
clear -o
owner |
memconfig |
clear -b
base -l
length |
DESCRIPTION
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.memconfig 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
memconfig program does not attempt to enforce these
rules, however the system will reject any attempt to set an illegal
combination.
The operands and their options are as follows:
- list
- List range slots.
-a- List all range slots, even those that are inactive.
- set
- Set memory range attributes.
-bbase- Memory range base address.
-llength- Length of memory range in bytes, power of 2.
-oowner- Text identifier for this setting (7 char max).
- attribute
- Attributes applied to this range; combinations of force, uncacheable, write-combine, write-through, write-back, or write-protect.
- clear
- Clear memory range attributes. Ranges may be cleared by owner or by
base/length combination.
To clear based on ownership:
-oowner- All ranges with this owner will be cleared.
To clear based on the base/length combination:
-bbase- Memory range base address.
-llength- Length of memory range in bytes, power of 2.
Base and length must exactly match an existing range.
SEE ALSO
HISTORY
memconfig was originally introduced in
FreeBSD 3.3 as
memcontrol.