QoS and Energy Management Coordination using Discrete Controller - PowerPoint PPT Presentation

. . QoS and Energy Management Coordination using Discrete Controller Synthesis . . . . . Noël De Palma Gwenaël Delaval Eric Rutten Grenoble University, INRIA Grenoble nov. 29, 2010 — GCM 2010, Bangalore

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Self-management for green computing green computing in distributed infrastructures grids, clouds, clusters; replication and multi-tiers trade-off with more traditional performance issues: dependability, scalability

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Self-management for green computing green computing in distributed infrastructures grids, clouds, clusters; replication and multi-tiers trade-off with more traditional performance issues: dependability, scalability autonomic computing and self-management approach for QoS: acting on admission control, resource provisioning, service degradation for energy: acting on frequency or voltage, state of hardware devices, server consolidation (virtualization)

. . . . . . . . . Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Control techniques for autonomic computing classical control techniques for individual issues, not for coordination

. . . . . . . . . Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Control techniques for autonomic computing classical control techniques for individual issues, not for coordination discrete controller synthesis (DCS): off-line computation from: a behavior model (FSM) controllables variables (degrees of freedom) a temporal property of a controller that, combined with the behavior, will enforce the objective, whatever the uncontrollable inputs

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Control techniques for autonomic computing classical control techniques for individual issues, not for coordination discrete controller synthesis (DCS): off-line computation from: a behavior model (FSM) controllables variables (degrees of freedom) a temporal property of a controller that, combined with the behavior, will enforce the objective, whatever the uncontrollable inputs advantages: . . . automatic generation of coordination manager 1 . . . ease of evolution in strategy 2 . . . correct by construction 3

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Control techniques for autonomic computing classical control techniques for individual issues, not for coordination discrete controller synthesis (DCS): off-line computation from: a behavior model (FSM) controllables variables (degrees of freedom) a temporal property of a controller that, combined with the behavior, will enforce the objective, whatever the uncontrollable inputs advantages: . . . automatic generation of coordination manager 1 . . . ease of evolution in strategy 2 . . . correct by construction 3 contributions: applying DCS to model and solve a problem of autonomic administration, of QoS and energy

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Reactive systems and automata modelling formalism and programming language reaction to input flows → output flows data-flow nodes and equations mode automata (FSM) parallel and hierarchical composition synchronous languages, (25+ years) tools: compilers (e.g., Heptagon), code generation, verification, ...

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Reactive systems and automata modelling formalism and programming language reaction to input flows → output flows data-flow nodes and equations mode automata (FSM) parallel and hierarchical composition synchronous languages, (25+ years) tools: compilers (e.g., Heptagon), code generation, verification, ... example : computing task control, delayable node delayable(r,c,e:bool) returns (a,s:bool) delayable(r,c,e) = a,s let automaton r and not c state Idle do a = false a = false; s = r and c Idle Wait a = false until r and c then Active | r and not c then Wait e r and c/s state Wait do a = false; s = c c/s until c then Active Active a = true state Active do a = true; s=false until e then Idle end tel

. . . . . . . . . Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Discrete controller synthesis: principle . Goal . . . Enforcing a temporal property Φ on a system (on which Φ does not a priori hold) . . . . .

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Discrete controller synthesis: principle . Goal . . . Enforcing a temporal property Φ on a system (on which Φ does not a priori hold) . . . . . . Principle (on implicit equational representation) . . . State memory Trans transition function Trans State Out Y Z Out output function . . . . .

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Discrete controller synthesis: principle . Goal . . . Enforcing a temporal property Φ on a system (on which Φ does not a priori hold) . . . . . . Principle (on implicit equational representation) . . . State memory Y c Trans transition function Trans State Y u Out Y Z Out output function Partition of inputs into controllable ( Y c ) and uncontrollable ( Y u ) inputs . . . . .

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . Discrete controller synthesis: principle . Goal . . . Enforcing a temporal property Φ on a system (on which Φ does not a priori hold) . . . . . . Principle (on implicit equational representation) . . . State memory Y c Trans transition function Ctrlr Trans State Y u Out Y Z Out output function Partition of inputs into controllable ( Y c ) and uncontrollable ( Y u ) inputs Computation of a controller such that the controlled system satisfies Φ . . . . . DCS tool: Sigali (H. Marchand e.a.)

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . BZR: contracts and DCS f ( x 1 , . . . , x n ) = ( y 1 , . . . , y p ) assume e A enforce e G with c 1 , . . . , c q y 1 = f 1 ( x 1 , . . . , x n , c 1 , . . . , c q ) · · · y p = f p ( x 1 , . . . , x n , c 1 , . . . , c q ) built on top of nodes in Heptagon (M. Pouzet e.a.) to each contract, associate controllable additional variables, local to the component

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . BZR: contracts and DCS f ( x 1 , . . . , x n ) = ( y 1 , . . . , y p ) contract assume e A enforce e G TrC StC OutC e A , e G with c 1 , . . . , c q body y 1 = f 1 ( x 1 , . . . , x n , c 1 , . . . , c q ) Y c Ctrlr · · · Trans State Y Out y p = f p ( x 1 , . . . , x n , c 1 , . . . , c q ) Z built on top of nodes in Heptagon (M. Pouzet e.a.) to each contract, associate controllable additional variables, local to the component at compile-time (user-friendly DCS), compute a controller for each component

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . BZR: contracts and DCS f ( x 1 , . . . , x n ) = ( y 1 , . . . , y p ) contract assume e A enforce e G TrC StC OutC e A , e G body y 1 = f 1 ( x 1 , . . . , x n ) Y c Ctrlr · · · Trans State Y Out y p = f p ( x 1 , . . . , x n ) Z built on top of nodes in Heptagon (M. Pouzet e.a.) to each contract, associate controllable additional variables, local to the component at compile-time (user-friendly DCS), compute a controller for each component when no controllables : verification by model-checking

Motivation Reactive systems and DCS QoS and energy management Synchronous controller design Conclusion . . . . . . . . . . . . . . . . BZR example mutual exclusion enforced by DCS in BZR two instances of the delayable node declaration of c 1 and c 2 as controllable variables simple contract: twotasks ( r 1 , e 1 , r 2 , e 2 ) = a 1 , s 1 , a 2 , s 2 enforce not ( a 1 and a 2 ) with c 1 , c 2 ( a 1 , s 1 ) = delayable ( r 1 , c 1 , e 1 ) ( a 2 , s 2 ) = delayable ( r 2 , c 2 , e 2 ) some requests r i are blocked, and memorized