linux-toradex.git/Documentation/sysctl/vm.txt, branch v3.6.8

Documentation: fix the VM knobs descritpion WRT pdflush

2012-08-04T08:15:09+00:00

The pdflush thread is long gone, however we still mention it incorrectly in the
kernel documentation. This patch fixes the situation.

Cc: Randy Dunlap 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: Al Viro

mm, oom: replace some information in tasklist dump

2012-08-01T01:42:42+00:00

The number of ptes and swap entries are used in the oom killer's badness
heuristic, so they should be shown in the tasklist dump.

This patch adds those fields and replaces cpu and oom_adj values that are
currently emitted.  Cpu isn't interesting and oom_adj is deprecated and
will be removed later this year, the same information is already displayed
as oom_score_adj which is used internally.

At the same time, make the documentation a little more clear to state this
information is helpful to determine why the oom killer chose the task it
did to kill.

Signed-off-by: David Rientjes 
Cc: KAMEZAWA Hiroyuki 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: prepare for removal of obsolete /proc/sys/vm/nr_pdflush_threads

2012-08-01T01:42:40+00:00

Since per-BDI flusher threads were introduced in 2.6, the pdflush
mechanism is not used any more.  But the old interface exported through
/proc/sys/vm/nr_pdflush_threads still exists and is obviously useless.

For back-compatibility, printk warning information and return 2 to notify
the users that the interface is removed.

Signed-off-by: Wanpeng Li 
Cc: Wu Fengguang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

documentation: update how page-cluster affects swap I/O

2012-08-01T01:42:39+00:00

Fix of the documentation of /proc/sys/vm/page-cluster to match the
behavior of the code and add some comments about what the tunable will
change in that behavior.

Signed-off-by: Christian Ehrhardt 
Acked-by: Jens Axboe 
Reviewed-by: Minchan Kim 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

doc: fix 3 typos in sysctl/vm.txt

2011-04-06T14:09:35+00:00

Signed-off-by: Paul Bolle 
Signed-off-by: Jiri Kosina

doc: clarify the behaviour of dirty_ratio/dirty_bytes

2010-10-28T01:03:08+00:00

When dirty_ratio or dirty_bytes is written the other parameter is disabled
and set to 0 (in dirty_bytes_handler() / dirty_ratio_handler()).

We do the same for dirty_background_ratio and dirty_background_bytes.

However, in the sysctl documentation, we say that the counterpart becomes
a function of the old value, that is not correct.

Clarify the documentation reporting the actual behaviour.

Reviewed-by: Greg Thelen 
Acked-by: David Rientjes 
Signed-off-by: Andrea Righi 
Cc: Randy Dunlap 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

oom: enable oom tasklist dump by default

2010-08-10T03:44:56+00:00

The oom killer tasklist dump, enabled with the oom_dump_tasks sysctl, is
very helpful information in diagnosing why a user's task has been killed.
It emits useful information such as each eligible thread's memory usage
that can determine why the system is oom, so it should be enabled by
default.

Signed-off-by: David Rientjes 
Acked-by: KOSAKI Motohiro 
Cc: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Documentation/sysctl/vm.txt typo

2010-06-28T11:59:28+00:00

Fix trivial typo: duplicated word.

Signed-off-by: Kulikov Vasiliy 
Acked-by: Randy Dunlap 
Signed-off-by: Jiri Kosina

mm: compaction: add a tunable that decides when memory should be compacted and when it should be reclaimed

2010-05-25T15:06:59+00:00

The kernel applies some heuristics when deciding if memory should be
compacted or reclaimed to satisfy a high-order allocation.  One of these
is based on the fragmentation.  If the index is below 500, memory will not
be compacted.  This choice is arbitrary and not based on data.  To help
optimise the system and set a sensible default for this value, this patch
adds a sysctl extfrag_threshold.  The kernel will only compact memory if
the fragmentation index is above the extfrag_threshold.

[randy.dunlap@oracle.com: Fix build errors when proc fs is not configured]
Signed-off-by: Mel Gorman 
Signed-off-by: Randy Dunlap 
Cc: Rik van Riel 
Cc: Minchan Kim 
Cc: KOSAKI Motohiro 
Cc: Christoph Lameter 
Cc: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: compaction: add /proc trigger for memory compaction

2010-05-25T15:06:59+00:00

Add a proc file /proc/sys/vm/compact_memory.  When an arbitrary value is
written to the file, all zones are compacted.  The expected user of such a
trigger is a job scheduler that prepares the system before the target
application runs.

Signed-off-by: Mel Gorman 
Acked-by: Rik van Riel 
Reviewed-by: KAMEZAWA Hiroyuki 
Reviewed-by: Minchan Kim 
Reviewed-by: KOSAKI Motohiro 
Reviewed-by: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds