ksm: more on default values
Adjust the max_kernel_pages default to a quarter of totalram_pages, instead of nr_free_buffer_pages() / 4: the KSM pages themselves come from highmem, and even on a 16GB PAE machine, 4GB of KSM pages would only be pinning 32MB of lowmem with their rmap_items, so no need for the more obscure calculation (nor for its own special init function). There is no way for the user to switch KSM on if CONFIG_SYSFS is not enabled, so in that case default run to KSM_RUN_MERGE. Update KSM Documentation and Kconfig to reflect the new defaults. Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Izik Eidus <ieidus@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:

committed by
Linus Torvalds

parent
0eca52a927
commit
c73602ad31
@@ -224,7 +224,9 @@ config KSM
|
||||
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.
|
||||
See Documentation/vm/ksm.txt for more information: KSM is inactive
|
||||
until a program has madvised that an area is MADV_MERGEABLE, and
|
||||
root has set /sys/kernel/mm/ksm/run to 1 (if CONFIG_SYSFS is set).
|
||||
|
||||
config DEFAULT_MMAP_MIN_ADDR
|
||||
int "Low address space to protect from user allocation"
|
||||
|
Reference in New Issue
Block a user