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-rw-r--r--Documentation/kernel-parameters.txt5
-rw-r--r--Documentation/power/interface.txt15
-rw-r--r--Documentation/sysctl/vm.txt27
3 files changed, 40 insertions, 7 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 71d05f48172..766abdab94e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1363,6 +1363,11 @@ running once the system is up.
reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
+ reservetop= [IA-32]
+ Format: nn[KMG]
+ Reserves a hole at the top of the kernel virtual
+ address space.
+
resume= [SWSUSP]
Specify the partition device for software suspend
diff --git a/Documentation/power/interface.txt b/Documentation/power/interface.txt
index 4117802af0f..a66bec222b1 100644
--- a/Documentation/power/interface.txt
+++ b/Documentation/power/interface.txt
@@ -52,3 +52,18 @@ suspend image will be as small as possible.
Reading from this file will display the current image size limit, which
is set to 500 MB by default.
+
+/sys/power/pm_trace controls the code which saves the last PM event point in
+the RTC across reboots, so that you can debug a machine that just hangs
+during suspend (or more commonly, during resume). Namely, the RTC is only
+used to save the last PM event point if this file contains '1'. Initially it
+contains '0' which may be changed to '1' by writing a string representing a
+nonzero integer into it.
+
+To use this debugging feature you should attempt to suspend the machine, then
+reboot it and run
+
+ dmesg -s 1000000 | grep 'hash matches'
+
+CAUTION: Using it will cause your machine's real-time (CMOS) clock to be
+set to a random invalid time after a resume.
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 7cee90223d3..20d0d797f53 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -29,6 +29,7 @@ Currently, these files are in /proc/sys/vm:
- drop-caches
- zone_reclaim_mode
- min_unmapped_ratio
+- min_slab_ratio
- panic_on_oom
==============================================================
@@ -138,7 +139,6 @@ This is value ORed together of
1 = Zone reclaim on
2 = Zone reclaim writes dirty pages out
4 = Zone reclaim swaps pages
-8 = Also do a global slab reclaim pass
zone_reclaim_mode is set during bootup to 1 if it is determined that pages
from remote zones will cause a measurable performance reduction. The
@@ -162,18 +162,13 @@ Allowing regular swap effectively restricts allocations to the local
node unless explicitly overridden by memory policies or cpuset
configurations.
-It may be advisable to allow slab reclaim if the system makes heavy
-use of files and builds up large slab caches. However, the slab
-shrink operation is global, may take a long time and free slabs
-in all nodes of the system.
-
=============================================================
min_unmapped_ratio:
This is available only on NUMA kernels.
-A percentage of the file backed pages in each zone. Zone reclaim will only
+A percentage of the total pages in each zone. Zone reclaim will only
occur if more than this percentage of pages are file backed and unmapped.
This is to insure that a minimal amount of local pages is still available for
file I/O even if the node is overallocated.
@@ -182,6 +177,24 @@ The default is 1 percent.
=============================================================
+min_slab_ratio:
+
+This is available only on NUMA kernels.
+
+A percentage of the total pages in each zone. On Zone reclaim
+(fallback from the local zone occurs) slabs will be reclaimed if more
+than this percentage of pages in a zone are reclaimable slab pages.
+This insures that the slab growth stays under control even in NUMA
+systems that rarely perform global reclaim.
+
+The default is 5 percent.
+
+Note that slab reclaim is triggered in a per zone / node fashion.
+The process of reclaiming slab memory is currently not node specific
+and may not be fast.
+
+=============================================================
+
panic_on_oom
This enables or disables panic on out-of-memory feature. If this is set to 1,