Lines Matching refs:task

43  "deadline", to schedule tasks. A SCHED_DEADLINE task should receive
47  every time the task wakes up, the scheduler computes a "scheduling deadline"
49  scheduled using EDF[1] on these scheduling deadlines (the task with the
51  task actually receives "runtime" time units within "deadline" if a proper
56  that each task runs for at most its runtime every period, avoiding any
58  algorithm selects the task with the earliest scheduling deadline as the one
60  with the "traditional" real-time task model (see Section 3) can effectively
66   - Each SCHED_DEADLINE task is characterised by the "runtime",
69   - The state of the task is described by a "scheduling deadline", and
72   - When a SCHED_DEADLINE task wakes up (becomes ready for execution),
89   - When a SCHED_DEADLINE task executes for an amount of time t, its
95     task is descheduled / preempted);
97   - When the remaining runtime becomes less or equal than 0, the task is
100     time" for this task (see next item) is set to be equal to the current
104     throttled task, the scheduling deadline and the remaining runtime are
124  There are no limitations on what kind of task can exploit this new
129  A typical real-time task is composed of a repetition of computation phases
130  (task instances, or jobs) which are activated on a periodic or sporadic
132  Each job J_j (where J_j is the j^th job of the task) is characterised by an
136  time max_j{c_j} is called "Worst Case Execution Time" (WCET) for the task.
137  A real-time task can be periodic with period P if r_{j+1} = r_j + P, or
139  d_j = r_j + D, where D is the task's relative deadline.
140  The utilisation of a real-time task is defined as the ratio between its
142  the fraction of CPU time needed to execute the task.
149  multiple real-time tasks, the parameters of the i-th task are indicated
160  maximum tardiness of each task is smaller or equal than
166  real-time task is statically assigned to one and only one CPU), it is
171  If D_i != P_i for some task, then it is possible to define the density of
172  a task as C_i/min{D_i,T_i}, and EDF is able to respect all the deadlines
179  utilisations (it can be shown that task sets with utilisations slightly
186  the jobs' deadlines of a task are respected. In order to do this, a task
195  allows to respect the jobs' absolute deadlines for this task (this is what is
198  this task, as it is not possible to respect its temporal constraints.
225  of a "traditional" real-time task, and is also often referred to as
234  figure out how we want to manage SCHED_DEADLINE bandwidth at the task group
273  Specifying a periodic/sporadic task that executes for a given amount of
303  -deadline task cannot fork.
315  An example of a simple configuration (pin a -deadline task to CPU0)
316  follows (rt-app is used to create a -deadline task).
330  task affinity)