From: J. Bruce Fields

Signed-off-by: J. Bruce Fields
Documentation/sched-rt-group.txt | 59 --------------------------------------
Documentation/scheduler/00-INDEX | 2 +
2 files changed, 2 insertions(+), 59 deletions(-)
delete mode 100644 Documentation/sched-rt-group.txt

On Mon, Apr 07, 2008 at 02:26:32PM -0600, Jonathan Corbet wrote:
> J. Bruce Fields wrote:
> > These are just 3 small patches for your documentation tree.

> Thanks; unless somebody objects I'll pull them in. I may not resubmit
> the tree before 2.6.25 - got travel to do and it's not urgent - but I'll
> definitely put it up for the next merge window.

Thanks! Oh, also, I just noticed one more. But one could probably do
this all day....


diff --git a/Documentation/sched-rt-group.txt b/Documentation/sched-rt-group.txt
deleted file mode 100644
index 1c6332f..0000000
--- a/Documentation/sched-rt-group.txt
+++ /dev/null
@@ -1,59 +0,0 @@
-Real-Time group scheduling.
-The problem space:
-In order to schedule multiple groups of realtime tasks each group must
-be assigned a fixed portion of the CPU time available. Without a minimum
-guarantee a realtime group can obviously fall short. A fuzzy upper limit
-is of no use since it cannot be relied upon. Which leaves us with just
-the single fixed portion.
-CPU time is divided by means of specifying how much time can be spent
-running in a given period. Say a frame fixed realtime renderer must
-deliver 25 frames a second, which yields a period of 0.04s. Now say
-it will also have to play some music and respond to input, leaving it
-with around 80% for the graphics. We can then give this group a runtime
-of 0.8 * 0.04s = 0.032s.
-This way the graphics group will have a 0.04s period with a 0.032s runtime
-Now if the audio thread needs to refill the DMA buffer every 0.005s, but
-needs only about 3% CPU time to do so, it can do with a 0.03 * 0.005s
-= 0.00015s.
-The Interface:
-system wide:
-[ time is specified in us because the interface is s32; this gives an
- operating range of ~35m to 1us ]
-The period takes values in [ 1, INT_MAX ], runtime in [ -1, INT_MAX - 1 ].
-A runtime of -1 specifies runtime == period, ie. no limit.
-New groups get the period from /proc/sys/kernel/sched_rt_period_us and
-a runtime of 0.
-Settings are constrained to:
- \Sum_{i} runtime_{i} / global_period <= global_runtime / global_period
-in order to keep the configuration schedulable.
diff --git a/Documentation/scheduler/00-INDEX b/Documentation/scheduler/00-INDEX
index b5f5ca0..fc234d0 100644
--- a/Documentation/scheduler/00-INDEX
+++ b/Documentation/scheduler/00-INDEX
@@ -12,5 +12,7 @@ sched-domains.txt
- information on scheduling domains.
- How and why the scheduler's nice levels are implemented.
+ - real-time group scheduling.
- information on schedstats (Linux Scheduler Statistics).

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