config MMU_NOTIFIER
bool
+config KSM
+ bool "Enable KSM for page merging"
+ depends on MMU
+ help
+ Enable Kernel Samepage Merging: KSM periodically scans those areas
+ of an application's address space that an app has advised may be
+ mergeable. When it finds pages of identical content, it replaces
+ the many instances by a single resident page with that content, so
+ saving memory until one or another app needs to modify the content.
+ Recommended for use with KVM, or with other duplicative applications.
+ See Documentation/vm/ksm.txt for more information.
+
config DEFAULT_MMAP_MIN_ADDR
int "Low address space to protect from user allocation"
default 4096
For most ia64, ppc64 and x86 users with lots of address space
a value of 65536 is reasonable and should cause no problems.
On arm and other archs it should not be higher than 32768.
- Programs which use vm86 functionality would either need additional
- permissions from either the LSM or the capabilities module or have
- this protection disabled.
+ Programs which use vm86 functionality or have some need to map
+ this low address space will need CAP_SYS_RAWIO or disable this
+ protection by setting the value to 0.
This value can be changed after boot using the
/proc/sys/vm/mmap_min_addr tunable.