An Agent and Its Threads
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communication thread core thread Spawn N negotiation threads ... negotiation threads active inactive Initialize An Agent and Its Threads execution thread
description
An Agent and Its Threads. Initialize. Spawn N negotiation threads. inactive. active. communication thread. negotiation threads. execution thread. core thread. Communication Thread. Get message via socket. Message?. no. yes. Parse message. Message queue. - PowerPoint PPT Presentation
Transcript of An Agent and Its Threads
com
mun
icat
ion
thre
ad
core
thre
ad
Spawn Nnegotiation
threads
...
nego
tiat
ion
thre
ads
active
inactive
Initialize
An Agent and Its Threads
exec
utio
n th
read
Communication Thread
Get message via socket
Parse message
Message?
yes
no
Add tomessage
queue...
Message queue Accesses by other threadsof the agent
Execution Thread
Setup andReset
yes
no
Get first jobFrom queue
...Job queue
Accesses by core threadof the agent
job’s startTime<currentTime?Sleep
ApplyExecutionheuristics
Abandon?
Execute
no
yes
RemoveJob
Executed?
Wait for data to be uploaded
yes
Remove job
ApplyPersistenceheuristics
no
Commited?
Sleep
no
yes
from job queue
from job queue
Execution Thread: Execution Heuristics
Time ConflictIf the job is not a tracking task and the expected stop time is later than the start of the next job plus a predefined relax_time, then Abandon = true.
Negotiation ConflictIf the job is not a tracking task and the agent iscurrently initiating a tracking coalition, thenAbandon = true.
Look-Ahead ConflictIf the job is not a tracking task and the agent has atracking task already planned for the near future,then Abandon = true.
Execution Thread: Persistence Heuristics
Persistent CommitmentIf the job is a tracking task and tracking is stillviable, then Committed = true.
Execution Thread: Execution Behavior
SD1, SD2, SD3
Task type?
Searchand Detect
TargetDetected?
CalibrateSensor
TargetDetected?
C1, C2, C3
Do nothing SuccessI
MeasureInitial Target
TargetDetected?
M1, M2, M3
Track
TargetDisappeared
orTerminatedas planned
T1, T2, T3
Executed= true
Executed= true
Executed= true
Executed= true
Executed= true
Jobconfirmed?
yes
Executed= false
no
Core Thread
Setup
Check Messages
Check Tasks
Check Execution
Check Coalition
Core Thread: Setup
SetupProfile
Managerinitializes the agent’s statusand configures its neighbors
CommManager
sets up comm. channel with Radsim, createsa socket, allocates msg. queue, sets msg. observer,and activates receiver
TaskManager
ThinkManager
NegotiationManager
spawns all negotiation threads and links data toeach thread; CLIPS processes are forked and pre-defined templates and rules are loaded
RTSSManager
sets up data stream access for Real-Time Scheduling Service (RTSS) interface and registersthreads and agent process IDs
CBRManager
loads two case bases, for initiating and responding cases of negotiation
RadarManager
initializes the sensor that the agent controls,measures background noise for each sector, turns on the radar observer, adds all neighboringsensors to its radar model
has a lesser role now because the radar tasksare managed by the Execution Manager
ExecutionManager
sets up the execution thread and executes tasksoff the job queue
CoalitionManager initializes the coalition vector
Core Thread: Check Messages
Accessmessage
queue
msg. forprof?
Parsemessage
messagetype
yes
Check messagescompleted
no
A negotiation request
Check messagescompleted
ActiveNegotiation?
Discardmessage
no yes
An acknowledgment
Respondto request
Respondto ack
Core Thread: Check Messages: Respond to Ack
Ack type?
Confirm tracking
task
Confirm
completed
Discardtracking
task
Discard
acknowledgment
...Job queue
Core Thread: Check Messages: Respond to Request
CPU?
FeasibilityStudy
Feasible& neg. idle?
yes
no
request
no
already doing?
Agreeto request
yes
no
Declineto negotiate
Modifyrequest?
yes
yesno
ModifyRequest
Retrieve best casevia CBR
Upload data
Activatenegotiation
threads
threadactivated? completedno yes
Core Thread: Check Tasks (Negotiation Tasks Only)
Status?
Initiating &success
Negotiation task
CheckTasks
Completed
Download &UpdateData
StoreCase
UpdateCoalition
RemoveTask
Download &UpdateData
StoreCase
UpdateCoalition
RemoveTask
ClearNegotiation
Thread
Download &UpdateData
StoreCase
TransitionTask
Download &UpdateData
StoreCase
RemoveTask
Initiating &failure
Responding &success
Responding &failure
...Task queue
Core Thread: Check Tasks:Update Coalition
If the negotiation is successful, the update involves modifying the coalition informationto reflect the success.
If the negotiation is not successful, the updateremoves the coalition member (the negotiationpartner) from the coalition.
Core Thread: Check Tasks:Transition Task
CPU?yes
New task
no
ConfigureTracking
Task
ReorganizeThread
Allocation
InsertTask to
Job Queue...
Job queue
Clean upJob Queue
RemoveTask
Core Thread: Check Execution
A job iscompleted?
no
Execution thread’s current status
yes
CheckExecutionCompleted
Job type?
ClearExecution
Thread
ClearExecution
Thread
FinishMeasure
Init. Target
Clear Execution
Thread
Calibrate SensorOr Search and Detect
MeasureInitial Target
Tracking
Idle
Targetdetected?
HandleTarget
CheckExecutionCompleted
Core Thread: Handle Target
ConfigureMeasuring
Task
InsertTask to
Job Queue
Handletarget
completed
success?
Clean upJob Queue
yes
...
Job queue
Core Thread: Finish Measure Initial Target
Updatetarget w/
Radar Manager
Computesensor-sector
list
Determinesample size
Analyzefeasiblepartners
Initiatenegotiations
completed
Targetdetected?
completedno
Clear Execution
Thread
Execution thread’s current status
DownloadTarget
Information
yes
Core Thread: Initiate Negotiations
Retrievebest casevia CBR
completed
Uploaddata
Sort feasiblepartners(utility)
Neg.thread idle?
Activatenegotiation
thread
threadactivated?
yes
yes
no
no
Createnegotiation
task
Initializecoalition
For allpartners
Updatecoalition
Done
Add task totask queue...
Task queue
Core Thread: Check Coalition
decided?no
Coalition’s current status
yes
CheckCoalition
Completed
coalitionfulfilled?
Acknowledgeto DiscardCoalition
Acknowledgeto ConfirmCoalition
ConfigureTracking
Task
ConfirmCoalition
no
Send to allagreed coalitionmembers
DiscardCoalition
yes
Insert it toJob Queue
Clean upJob Queue
Confirmthe Task
Send to allagreed coalitionmembers
...
Job queue
Negotiation Thread
Setupand Reset
Wait to beactivated
Downloaddata
RespondingBehavior
Mode?
Responding to a negotiation request
Initiating a negotiation request
InitiatingBehavior
Updatedata
Wait fordata to be uploaded
Negotiation Thread: Initiating Behavior
Composefirst initiating
message
Done?
Done = no
SendMessage
Wait forresponse
response?
Parseresponse
React & ComposeMessage
no
yes
yes
noReact &composemessage
Negotiationcompleted
Check Coalition
abort?yes
no
time?expired
still okay
Negotiation Thread: Initiating Behavior:Check Coalition
If the coalition has gathered enough help forCPU reallocation, then Abort = true.
If the tracking coalition has been satisfied, thenAbort = true.
If the tracking coalition is no longer possible, then Abort = true.
Negotiation Thread: Initiating Behavior:React & Compose Message
type?
Response message
CheckCoalition
Acceptability
modify time
accept?
Failure
no
UpdateCoalition
Initiate
yesFailure
no goout of timestop
CheckCoalition
Acceptability
accept?
UpdateCoalition
Success
yes
counter
agree ComposeMore Info
more info
no
null?
Info_Null Info
yes no
Negotiation Thread: Responding Behavior
Composefirst responding
message
Done?
Done = no
SendMessage
Wait forresponse
response?
Parseresponse
React & ComposeMessage
no
yes
yes
noReact &composemessage
Negotiationcompleted
time?expired
still okay
ResetCLIPS
Negotiation Thread: Responding Behavior:React & Compose Message
type?
Response message
info
yes
abortout of timestop
yes
agree
yes
infonull
CLIPS:Rule-BasedReasoning
Computeevidencesupport
> persuas.thresh?
Agree
More Info
no
CPU?
no
ReactCPU
CPU?
Counter
Stop
no
Failure
Success
Negotiation Thread: Responding Behavior:React CPU
If the current CPU willing to give up is greater than or equal to the desired CPU (by theinitiator), and the desired CPU is smaller than or equal to the maximum CPU willing to give up, then Agree.
If the current CPU willing to give up is greaterthan the maximum CPU willing to give up, thenCounter with maximum CPU willing to give up.
If time allocated for the negotiation is runningout, then Counter. If the current CPU willing togive up is grater than the maximum CPU willing to give up, Counter with the latter value. Otherwise, Counter with the former.
