linux-toradex.git/Documentation/cgroups/blkio-controller.txt, branch v3.4.71

Documentation: Fix multiple typo in Documentation

2012-03-07T15:08:24+00:00

Signed-off-by: Masanari Iida 
Acked-by: Randy Dunlap 
Signed-off-by: Jiri Kosina

Documentation: fix cgroup blkio throttle filenames

2011-07-06T20:17:51+00:00

All the blkio.throttle.* file names are incorrectly reported without
".throttle" in the documentation. Fix it.

Signed-off-by: Andrea Righi 
Signed-off-by: Randy Dunlap 
Acked-by: Vivek Goyal 
Signed-off-by: Linus Torvalds

Documentation: fix cgroup typos and formatting

2011-06-16T04:52:50+00:00

Fix format and spelling.

Signed-off-by: Jörg Sommer 
Acked-by: Paul Menage 
Signed-off-by: Randy Dunlap 
Signed-off-by: Linus Torvalds

Documentation: update cgroupfs mount point

2011-06-16T04:52:50+00:00

According to commit 676db4af0430 ("cgroupfs: create /sys/fs/cgroup to
mount cgroupfs on") the canonical mountpoint for the cgroup filesystem
is /sys/fs/cgroup.  Hence, this should be used in the documentation.

Signed-off-by: Jörg Sommer 
Acked-by: Paul Menage 
Signed-off-by: Randy Dunlap 
Signed-off-by: Linus Torvalds

blk-cgroup: Lower minimum weight from 100 to 10.

2011-03-08T18:45:00+00:00

We've found that we still get good, useful isolation at weights this
low. I'd like to adjust the minimum so that any other changes can take
these values into account.

Signed-off-by: Justin TerAvest 
Acked-by: Vivek Goyal 
Signed-off-by: Jens Axboe

cfq-iosched: Always provide group isolation.

2011-03-01T20:05:08+00:00

Effectively, make group_isolation=1 the default and remove the tunable.
The setting group_isolation=0 was because by default we idle on
sync-noidle tree and on fast devices, this can be very harmful for
throughput.

However, this problem can also be addressed by tuning slice_idle and
possibly group_idle on faster storage devices.

This change simplifies the CFQ code by removing the feature entirely.

Signed-off-by: Justin TerAvest 
Acked-by: Vivek Goyal 
Signed-off-by: Jens Axboe

blk-cgroup: Allow creation of hierarchical cgroups

2010-11-15T18:37:36+00:00

o Allow hierarchical cgroup creation for blkio controller

o Currently we disallow it as both the io controller policies (throttling
  as well as proportion bandwidth) do not support hierarhical accounting
  and control. But the flip side is that blkio controller can not be used with
  libvirt as libvirt creates a cgroup hierarchy deeper than 1 level.

  //libvirt/qemu/

o So this patch will allow creation of cgroup hierarhcy but at the backend
  everything will be treated as flat. So if somebody created a an hierarchy
  like as follows.

			root
			/  \
		     test1 test2
			|
		     test3

  CFQ and throttling will practically treat all groups at same level.

				pivot
			     /  |   \  \
			root  test1 test2  test3

o Once we have actual support for hierarchical accounting and control
  then we can introduce another cgroup tunable file "blkio.use_hierarchy"
  which will be 0 by default but if user wants to enforce hierarhical
  control then it can be set to 1. This way there should not be any
  ABI problems down the line.

o The only not so pretty part is introduction of extra file "use_hierarchy"
  down the line. Kame-san had mentioned that hierarhical accounting is
  expensive in memory controller hence they keep it off by default. I
  suspect same will be the case for IO controller also as for each IO
  completion we shall have to account IO through hierarchy up to the root.
  if yes, then it probably is not a very bad idea to introduce this extra
  file so that it will be used only when somebody needs it and some people
  might enable hierarchy only in part of the hierarchy.

o This is how basically memory controller also uses "use_hierarhcy" and
  they also allowed creation of hierarchies when actual backend support
  was not available.

Signed-off-by: Vivek Goyal 
Acked-by: Balbir Singh 
Reviewed-by: Gui Jianfeng 
Reviewed-by: Ciju Rajan K 
Tested-by: Ciju Rajan K 
Signed-off-by: Jens Axboe

Merge branch 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block

2010-10-23T00:00:32+00:00

* 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block: (39 commits)
  cfq-iosched: Fix a gcc 4.5 warning and put some comments
  block: Turn bvec_k{un,}map_irq() into static inline functions
  block: fix accounting bug on cross partition merges
  block: Make the integrity mapped property a bio flag
  block: Fix double free in blk_integrity_unregister
  block: Ensure physical block size is unsigned int
  blkio-throttle: Fix possible multiplication overflow in iops calculations
  blkio-throttle: limit max iops value to UINT_MAX
  blkio-throttle: There is no need to convert jiffies to milli seconds
  blkio-throttle: Fix link failure failure on i386
  blkio: Recalculate the throttled bio dispatch time upon throttle limit change
  blkio: Add root group to td->tg_list
  blkio: deletion of a cgroup was causes oops
  blkio: Do not export throttle files if CONFIG_BLK_DEV_THROTTLING=n
  block: set the bounce_pfn to the actual DMA limit rather than to max memory
  block: revert bad fix for memory hotplug causing bounces
  Fix compile error in blk-exec.c for !CONFIG_DETECT_HUNG_TASK
  block: set the bounce_pfn to the actual DMA limit rather than to max memory
  block: Prevent hang_check firing during long I/O
  cfq: improve fsync performance for small files
  ...

Fix up trivial conflicts due to __rcu sparse annotation in include/linux/genhd.h

blkio: Documentation Update

2010-09-16T06:45:03+00:00

o Documentation update

Signed-off-by: Vivek Goyal 
Signed-off-by: Jens Axboe

cfq-iosched: Documentation help for new tunables

2010-08-23T10:25:29+00:00

Some documentation to provide help with tunables.

Signed-off-by: Vivek Goyal 
Acked-by: Jeff Moyer 
Signed-off-by: Jens Axboe