- dirty_background_ratio
- dirty_expire_centisecs
- dirty_writeback_centisecs
+- highmem_is_dirtyable (only if CONFIG_HIGHMEM set)
- max_map_count
- min_free_kbytes
- laptop_mode
- min_unmapped_ratio
- min_slab_ratio
- panic_on_oom
+- oom_dump_tasks
+- oom_kill_allocating_task
- mmap_min_address
+- numa_zonelist_order
+- nr_hugepages
+- nr_overcommit_hugepages
==============================================================
dirty_ratio, dirty_background_ratio, dirty_expire_centisecs,
-dirty_writeback_centisecs, vfs_cache_pressure, laptop_mode,
-block_dump, swap_token_timeout, drop-caches:
+dirty_writeback_centisecs, highmem_is_dirtyable,
+vfs_cache_pressure, laptop_mode, block_dump, swap_token_timeout,
+drop-caches, hugepages_treat_as_movable:
See Documentation/filesystems/proc.txt
value for each lowmem zone in the system. Each lowmem zone gets
a number of reserved free pages based proportionally on its size.
+Some minimal ammount of memory is needed to satisfy PF_MEMALLOC
+allocations; if you set this to lower than 1024KB, your system will
+become subtly broken, and prone to deadlock under high loads.
+
+Setting this too high will OOM your machine instantly.
+
==============================================================
percpu_pagelist_fraction
1 and 2 are for failover of clustering. Please select either
according to your policy of failover.
+=============================================================
+
+oom_dump_tasks
+
+Enables a system-wide task dump (excluding kernel threads) to be
+produced when the kernel performs an OOM-killing and includes such
+information as pid, uid, tgid, vm size, rss, cpu, oom_adj score, and
+name. This is helpful to determine why the OOM killer was invoked
+and to identify the rogue task that caused it.
+
+If this is set to zero, this information is suppressed. On very
+large systems with thousands of tasks it may not be feasible to dump
+the memory state information for each one. Such systems should not
+be forced to incur a performance penalty in OOM conditions when the
+information may not be desired.
+
+If this is set to non-zero, this information is shown whenever the
+OOM killer actually kills a memory-hogging task.
+
+The default value is 0.
+
+=============================================================
+
+oom_kill_allocating_task
+
+This enables or disables killing the OOM-triggering task in
+out-of-memory situations.
+
+If this is set to zero, the OOM killer will scan through the entire
+tasklist and select a task based on heuristics to kill. This normally
+selects a rogue memory-hogging task that frees up a large amount of
+memory when killed.
+
+If this is set to non-zero, the OOM killer simply kills the task that
+triggered the out-of-memory condition. This avoids the expensive
+tasklist scan.
+
+If panic_on_oom is selected, it takes precedence over whatever value
+is used in oom_kill_allocating_task.
+
+The default value is 0.
+
==============================================================
mmap_min_addr
vast majority of applications to work correctly and provide defense in depth
against future potential kernel bugs.
+==============================================================
+
+numa_zonelist_order
+
+This sysctl is only for NUMA.
+'where the memory is allocated from' is controlled by zonelists.
+(This documentation ignores ZONE_HIGHMEM/ZONE_DMA32 for simple explanation.
+ you may be able to read ZONE_DMA as ZONE_DMA32...)
+
+In non-NUMA case, a zonelist for GFP_KERNEL is ordered as following.
+ZONE_NORMAL -> ZONE_DMA
+This means that a memory allocation request for GFP_KERNEL will
+get memory from ZONE_DMA only when ZONE_NORMAL is not available.
+
+In NUMA case, you can think of following 2 types of order.
+Assume 2 node NUMA and below is zonelist of Node(0)'s GFP_KERNEL
+
+(A) Node(0) ZONE_NORMAL -> Node(0) ZONE_DMA -> Node(1) ZONE_NORMAL
+(B) Node(0) ZONE_NORMAL -> Node(1) ZONE_NORMAL -> Node(0) ZONE_DMA.
+
+Type(A) offers the best locality for processes on Node(0), but ZONE_DMA
+will be used before ZONE_NORMAL exhaustion. This increases possibility of
+out-of-memory(OOM) of ZONE_DMA because ZONE_DMA is tend to be small.
+
+Type(B) cannot offer the best locality but is more robust against OOM of
+the DMA zone.
+
+Type(A) is called as "Node" order. Type (B) is "Zone" order.
+
+"Node order" orders the zonelists by node, then by zone within each node.
+Specify "[Nn]ode" for zone order
+
+"Zone Order" orders the zonelists by zone type, then by node within each
+zone. Specify "[Zz]one"for zode order.
+
+Specify "[Dd]efault" to request automatic configuration. Autoconfiguration
+will select "node" order in following case.
+(1) if the DMA zone does not exist or
+(2) if the DMA zone comprises greater than 50% of the available memory or
+(3) if any node's DMA zone comprises greater than 60% of its local memory and
+ the amount of local memory is big enough.
+
+Otherwise, "zone" order will be selected. Default order is recommended unless
+this is causing problems for your system/application.
+
+==============================================================
+
+nr_hugepages
+
+Change the minimum size of the hugepage pool.
+
+See Documentation/vm/hugetlbpage.txt
+
+==============================================================
+
+nr_overcommit_hugepages
+
+Change the maximum size of the hugepage pool. The maximum is
+nr_hugepages + nr_overcommit_hugepages.
+
+See Documentation/vm/hugetlbpage.txt
projects / linux-2.6-omap-h63xx.git / blobdiff