diff options
Diffstat (limited to 'Documentation/scheduler')
| -rw-r--r-- | Documentation/scheduler/sched-deadline.txt | 6 | ||||
| -rw-r--r-- | Documentation/scheduler/sched-rt-group.txt | 8 |
2 files changed, 10 insertions, 4 deletions
diff --git a/Documentation/scheduler/sched-deadline.txt b/Documentation/scheduler/sched-deadline.txt index 8e37b0ba2c9d..cbc1b46cbf70 100644 --- a/Documentation/scheduler/sched-deadline.txt +++ b/Documentation/scheduler/sched-deadline.txt @@ -408,6 +408,11 @@ CONTENTS * the new scheduling related syscalls that manipulate it, i.e., sched_setattr() and sched_getattr() are implemented. + For debugging purposes, the leftover runtime and absolute deadline of a + SCHED_DEADLINE task can be retrieved through /proc/<pid>/sched (entries + dl.runtime and dl.deadline, both values in ns). A programmatic way to + retrieve these values from production code is under discussion. + 4.3 Default behavior --------------------- @@ -476,6 +481,7 @@ CONTENTS Still missing: + - programmatic way to retrieve current runtime and absolute deadline - refinements to deadline inheritance, especially regarding the possibility of retaining bandwidth isolation among non-interacting tasks. This is being studied from both theoretical and practical points of view, and diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt index a03f0d944fe6..d8fce3e78457 100644 --- a/Documentation/scheduler/sched-rt-group.txt +++ b/Documentation/scheduler/sched-rt-group.txt @@ -158,11 +158,11 @@ as its prone to starvation without deadline scheduling. Consider two sibling groups A and B; both have 50% bandwidth, but A's period is twice the length of B's. -* group A: period=100000us, runtime=10000us - - this runs for 0.01s once every 0.1s +* group A: period=100000us, runtime=50000us + - this runs for 0.05s once every 0.1s -* group B: period= 50000us, runtime=10000us - - this runs for 0.01s twice every 0.1s (or once every 0.05 sec). +* group B: period= 50000us, runtime=25000us + - this runs for 0.025s twice every 0.1s (or once every 0.05 sec). This means that currently a while (1) loop in A will run for the full period of B and can starve B's tasks (assuming they are of lower priority) for a whole |