Post on 12-Nov-2014
description
Schedulability analysis using Uppaaland Uppaal SMC in CRAFTERS
Abdeldjalil Boudjadar,Alexandre David,Jin Hyun Kim,Kim G. Larsen,Marius Mikucionis,Ulrik Nyman,Arne Skou
InfinIT Talk 12th of March 2014
CRAFTERS project
Title ConstRaint and Application driven Frameworkfor Tailoring Embedded Real-time Systems.
Period Jun 2012 - May 2015Website www.crafters-project.orgPeople Two Post Docs @AAU
Partners 25
CRAFTERS project
Goals As direct effects of the project results30% reduction of the total cost of ownership,50% shorter time-to-market, and30% decrease of the number of development
assets are expected.
AAU contributions
Deliverables
• Model transformations (UML -> Uppaal)• Real-time testing tool, Uppaal TRON
Research
• New research on schedulability analysis
Publications
FACS 2013 Hierarchical Scheduling Framework Based onCompositional Analysis Using Uppaal(Published)
ERTS22014 Schedulability and Energy Efficiency forMulti-core Hierarchical Scheduling Systems(Published)
Submitted1 Statistical Model Checking for ImprovedResource Utilization in Hierarchical SchedulingSystems
Submitted2 Degree of Schedulability of Mixed-CriticalityReal-time Systems with Probability-basedSporadic Tasks
A hierarchical scheduling system
System
Component1 Component2
task1 task2 task3 task4 task5
RM
(100,37)
EDF
EDF
(70,25)
(250,40) (400,50) (140,7) (150,7) (300,30)
Figure: Example of hierarchical scheduling system.
Schedulability analysis
?? Do you use hierarchical scheduling??? How do you perform schedulability analysis?
Motivation Separation of concerns. ReComp.
Schedulability analysis
sbfΓ(t) =
⌊t − (Π−Θ)
Π
⌋·Θ + εs (1)
where
εs = max(
t − 2(Π−Θ)− Π
⌊t − (Π−Θ)
Π
⌋, 0). (2)
FACS 2013
SystemEDF
Component1 Component2
task1 task2 task3 task4
EDF,.RM:.scheduling.policies..A,.A1,.A2:.analysis.processes.
A
A1 A2
task5
EDF RM
Figure: Compositional analysis.
Submitted1
∀t ∈ ]0; 2 · LCMW ] : dbfW (t) ≤ sbfΓ(t) (3)
FACS 2013
supplying_time[supid]'==0&& curTime <= sup[supid].prd - sup[supid].budget + supplying_time[supid]&& curTime <= sup[supid].prd
stop_supplying[supid]!
replenishment[supid]!
supplying_time[supid]'==1&& supplying_time[supid]<=sup[supid].budget
curTime <=sup[supid].prd && supplying_time[supid]'==0
NotSupplying
curTime ==sup[supid].prd
curTime < sup[supid].prd -sup[supid].budget + supplying_time[supid]stop_supplying[supid]!
supplying_time[supid]>=sup[supid].budget
start_supplying[supid]!supplying_time[supid]<=sup[supid].budget
supplying[supid]=1Supplying
supplying[supid]=1
supplying[supid]=0
Donesupplying[supid]=0
curTime=0, supplying_time[supid]=0,supplying[supid]=0
Figure: Non-deterministic supplier template
FACS 2013
Listing 1: Data structure for timed actionconst cmd_set_t Target_tracking = {
{ INPUT , 3, 110, 122, 0},{ INPUT , 3, 164, 182, 0},{ INPUT , 3, 100, 122, 0},{ INPUT , 3, 146, 162, 0},{ COMPUTE , 0, 3600, 4000, 0},{ OUTPUT , 3, 200, 222, 0},{ OUTPUT , 3, 146, 162, 0},FIN ,FIN ,FIN ,FIN ,FIN
};
const cmd_set_t Target_sweetening = {{ INPUT , 3, 110, 122, 0},{ COMPUTE , 0, 1800, 2000, 0},FIN ,FIN ,FIN ,FIN ,FIN ,FIN ,FIN ,FIN ,FIN ,FIN
};
ERTS2 2014: Vision
Schedulability requirements
Energy consumption
Hierarchical system architecture
L _
_
_
T2
S
C1 C2
T1 T3 T4
UPPAAL Network of Parameterized
Stopwatch Automata
Schedulability analysis(model
checking)
Energy efficiency(Stochastic model
checking)
SMC
Schedulable: yes / no
Energyprofile
Con
crete
task
beh
avio
r
Con
crete
task
beh
avio
r
CPU1 CPU2
Figure: Overview of the analysis framework
ERTS2 2014: Vision
Schedulability requirements
Energy consumption
Hierarchical system architecture
L _
_
_
T2
S
C1 C2
T1 T3 T4
UPPAAL Network of Parameterized
Stopwatch Automata
Schedulability analysis(model
checking)
Energy efficiency(Stochastic model
checking)
SMC
Schedulable: yes / no
Energyprofile
Con
crete
task
beh
avio
r
Con
crete
task
beh
avio
r
CPU1 CPU2
Figure: Overview of the analysis framework
ERTS2 2014: Case study
Avionics
Hard-Subsystem
( 25, insuf, EDF)
Controls and Display
(20, 15, FP )
Targeting
(40, 23, FP) Navigation
(30, 11, EDF)
Weapon Ctrl.
(10, 8, FP) HUD Display
T9(50,6,50)
MPD Display
T10(50,8,50)
MPD Button Resp.
T11(200,1,200)
Change Display
T12 (200,1,200)
Flight Data
T1(50,8,50)
Steering
T2(80,6,80)
Target Tracking
T3(40,4,40)
Target Sweetening
T4(40,2,40)
AUTO/CCIP Toggle
T5(200,1,200)
Weapon Release
T8(10,1,5)
Weapon Trajectory
T6 (100,7,100)
Reinitiate Trajectory
T7(400,6,400) insuf : insufficient budget
Figure: Architecture of the hierarchical scheduling system
ERTS2 2014: Cumulated energyconsumption
Energy ConsumptionTask 2 ExecutionTask 1 Execution
time
valu
e
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
0 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690
Simulations (1)
Figure: Cumulated energy consumption for two individual tasks
ERTS2 2014: Energy profile
Figure: Energy profile for two tasks, 1000 runs, 1000000 time units
Submitted1
Submitted1 Statistical Model Checking for ImprovedResource Utilization in Hierarchical SchedulingSystems
• Comparison with conventional method.• Discovered error in conventional tool CARTS.
Confirmed by tool makers.
Comparison of schedulability analysis ofCARTS and Uppaal models
Comp Tasks P, WCET CARTS SMCEDF RM EDF RM
S1T1 500, 30 100, 32.5 100, 32.5 100, 33 100, 33T2 500, 100
S2T1 170, 30 100, 46.67 100, 47.5 100, 46 100, 48T2 500, 100
S3T1 250, 40 150, 42.5 150, 42.5 150, 45 150, 45T2 750, 50
S4
T1 80000, 6890 50000, 15082 50000, 15082 50000, 15082 50000, 15082T2 100000, 8192T3 200000, 2644 10000, 1880 10000, 2155.6 10000, 1875 10000, 2155T4 1000000, 5874
Task synchronization
Submitted2
Submitted2 Degree of Schedulability of Mixed-CriticalityReal-time Systems with Probability-basedSporadic Tasks
• Mixed criticality• Sporadic tasks• Simulation
Sporadic task and events
Event patterns
Missing deadlines
Figure: Execution of a sporadic task
PoMD
Definition (Percentage of Missed Deadlines)The PoMD of an entity X for a run π is given by:
PoMDX (π) = (lim supt→∞
Misst (X , π)
Trigt (X , π))× 100
DoQoS
Definition (Degradation of Quality of Service)The DoQoS of a task Ti over a finite set of runs Π is definedas:
DoQoSTi (Π) =
{0 if limt→∞
∑π∈Π Misst (Ti , π) = 0
limt→∞
∑π∈Π Overrunt (Ti ,π)∑
π∈Π Misst (Ti ,π) Otherwise
Sched◦
Definition (The degree of schedulability )We define the Sched◦ of an entity in terms of two factorsSched◦
P and Sched◦D to be given by:
Sched◦P =
{∞ if PoMD = 0
1PoMD Otherwise
}
Sched◦D =
{∞ if DoQoS = 0
1DoQoS Otherwise
}
Sufficient budget
Table: The degree of schedulability of tasks under periodicevents
Component ((40, 23), FPS) PoMD DoQoST p
3 (40, 4), 0 0T s
4(40, 2), 0 0
Case study
Avionics
Hard-Subsystem
( 25, insuf, EDF)
Controls and Display
(20, 15, FP )
Targeting
(40, 23, FP) Navigation
(30, 11, EDF)
Weapon Ctrl.
(10, 8, FP) HUD Display
T9(50,6,50)
MPD Display
T10(50,8,50)
MPD Button Resp.
T11(200,1,200)
Change Display
T12 (200,1,200)
Flight Data
T1(50,8,50)
Steering
T2(80,6,80)
Target Tracking
T3(40,4,40)
Target Sweetening
T4(40,2,40)
AUTO/CCIP Toggle
T5(200,1,200)
Weapon Release
T8(10,1,5)
Weapon Trajectory
T6 (100,7,100)
Reinitiate Trajectory
T7(400,6,400) insuf : insufficient budget
Figure: Architecture of the hierarchical scheduling system
Generic Avionics Components and Tasks
Component Criticality Ti ei pi di Importance
Navigation Hard Aircraft flight data(T p1 ) 8 50(55) critical
critical Steering(T p2 ) 6 80 critical
Targeting Hard Target tracking(T p3 ) 4 40 critical
critical Target sweetening(T s4) 2 40 critical
AUTO/CCIP toggle(T s5) 1 200 critical
Weapon Hard Weapon trajectory(T p6 ) 7 100 critical
Control non-critical Reinitiate trajectory(T s7) 6 400 essential
Weapon release(T p8 ) 1 10 5 critical
Soft
HUD display(T p9 ) 6 55(52) essential
Controls & MPD tactical display(T p10) 8 50(52) essential
Displays MPD button response (T s11) 1 200 background
Change display mode (T s12) 1 200 background
Schedulability degree of componentControls & Displays
Task Sched◦ Budget=14 Budget=17 Budget=19 Budget=20
HUD Display(T9) DoQoS 0.004±0.003 0 0 0PoMD 0.004±0.004 0 0 0
MPD Display(T10) DoQoS 3.068±0.151 0.343±0.052 0.003±0.003 0PoMD 0.231±0.018 0.002±0.002 0.0005±0 0
MPD Button(T11) DoQoS 0 0 0 0PoMD 0 0 0 0
Change Mode(T12) DoQoS 0 0 0 0PoMD 0 0 0 0
ERTS2 2014: Vision
Schedulability requirements
Energy consumption
Hierarchical system architecture
L _
_
_
T2
S
C1 C2
T1 T3 T4
UPPAAL Network of Parameterized
Stopwatch Automata
Schedulability analysis(model
checking)
Energy efficiency(Stochastic model
checking)
SMC
Schedulable: yes / no
Energyprofile
Con
crete
task
beh
avio
r
Con
crete
task
beh
avio
r
CPU1 CPU2
Figure: Overview of the analysis framework