Seong-lae ChoIt is Deadlock Avoidance itself
Define a set of vectors and matrices that characterize the current state of all resources and processes
Each process must a priori claim maximum use
DataStructure
- n - process number, m resource type number.
- Available : one dimension array of length m - store available resources number by resource type
- Max (require to retire process): two dimension array of m x n - process i require j type and express it by max[i,j]
- Allocation : two dimension array of m x n - how much allocated - allocation[i,j]
- Need : two dimension array of m x n - (Need = Max - Allocation) how much more need
Banker's algorithm is function of input Request
Request_i : one dimension array of length m - request vector for process Pi
Safety Algorithm
Work(copy of Available) and Finish(initialized false for all process) be vectors of length m and n, respectively → fine sequence of execution
Result is no → process must wait
Difference
All tow algorithm is Deterministic Algorithm but Banker's is determine for Allocation
Detection is determine of checking deadlock
- Banker's Algorithm is virtual verification of unassigned resource by simulation
- Detection Algorithm is check stage is safe or not