The '''Ricart-Agrawala Algorithmalgorithm''' is an algorithm for [[mutual exclusion]] on a [[distributed system]]. This algorithm is an extension and optimization of [[Lamport's Distributed Mutual Exclusion Algorithm]], by removing the need for <math>ack</math> messages<ref>{{cite journal|last1=Ricart|first1=Glenn|last2=Agrawala|first2=Ashok K.|title=An optimal algorithm for mutual exclusion in computer networks|journal=Communications of the ACM|date=1 January 1981|volume=24|issue=1|pages=9–17|doi=10.1145/358527.358537|url=https://dl.acm.org/citation.cfm?id=358537|ref=origpaper}}</ref>. It was developed by [[Glenn Ricart]] and [[Ashok Agrawala]].
==Algorithm==
Line 27:
* Synchronization Delays: One message propagation delay
===Common Optimizationsoptimizations===
Once site <math>P_i</math> has received a <math>reply</math> message from site <math>P_j</math>, site <math>P_i</math> may enter the critical section multiple times without receiving permission from <math>P_j</math> on subsequent attempts up to the moment when <math>P_i</math> has sent a <math>reply</math> message to <math>P_j</math>. This is called Roucairol-Carvalho optimization or Roucairol-Carvalho algorithm.
