© j. christopher beck 20081 lecture 30: distributed scheduling
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© J. Christopher Beck 2008 2
Outline Overview & Example
Supply Chain Distributed Scheduling Exercise
Distributed Timetabling Optimization and information
engineering issues
© J. Christopher Beck 2008 3
Readings
Gaspero, Mizzaro, & Schaerf, A MultiAgent Architecture for Distributed Course Timetabling, Sixth International Workshop on Distributed Constraint Reasoning, 2005
© J. Christopher Beck 2008 4
Distributed Scheduling
Same as “normal” scheduling except there are multiple decision makers may control different resources and/or
have different sets of jobs to execute local problems are inter-dependent
Why distributed? real problem is distributed for
geographical, political, or organizational reasons
© J. Christopher Beck 2008 6
Distributed Scheduling
Local decisions depend on and effect external events Need to coordinate schedules with
suppliers and consumers! Local decision maker has no control
over others’ schedules
© J. Christopher Beck 2008 7
Distributed Scheduling Exercise: Resource Agent
You control some units of a resource RED, YELLOW, GREEN,
BLUE Your goal is to sell
the resource at the highest price possible
© J. Christopher Beck 2008 8
Distributed Scheduling Exercise: Job Agent
You have activities to perform that need resources
You have $1000 to spend buying resources
Your goal is to buy the resources required for all your activities for the least cost
© J. Christopher Beck 2008 9
Distributed Scheduling Exercise
To sell/buy a resource agents must sign each others sheet noting quantity and price
Once you have a verbal agreement – you must sign!
© J. Christopher Beck 2008 11
Distributed Timetabling Problem
(See Gaspero et al. paper) University classroom scheduling Each department “owns” a set of
classrooms Each department has a set of
courses to schedule Class size, A/V requirements, etc.
© J. Christopher Beck 2008 12
Distributed Timetabling Problem
Doesn’t have to be distributed Departments can make their own
schedules and ignore everyone else But, if they share rooms maybe
everyone can have a better schedule No department is willing to give up
authority for its classrooms Centralized solution is politically
impossible
© J. Christopher Beck 2008 13
Distributed Timetabling Solution
Decide on a currency one student not being able to take a
course = 1 unit of currency What do they trade?
roomslots: use a room for a time slot
© J. Christopher Beck 2008 14
Distributed Timetabling Solution
Somewhat ad hoc solution each department creates its own schedule then a semi-market mechanism is used to
trade roomslots to try an improve schedules
You should have a general understanding of the problem solved and the techniques in this paper
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