Performance Analysis of Singhal-Kshemkalyani’s Implementation of Vector Clock

1. Performance Analysis of Singhal-Kshemkalyani’s Implementation of Vector Clock MD IFTAKHARUL ISLAM Computer Science, Kent State University

2. Vector Clock Example e13 e11 e12 P1 (1,0,0) (2,0,0) (3,6,1) • “enn” is event; “(n,n,n)” is clock value e21 e22 e23 e24 P2 (0,1,0) (2,3,0) (2,5,1) (2,4,1) e31 e32 P3 (0,0,1) (0,0,2)

3. Singhal-Kshemkalyani’s VC example • when P3 needs to send a message to P2 (state 1), it only needs to send entries for P3 and P5

4. Experimental Setup • Ring topology of processes • The process has three command actions • Local Event • Send Messages • Receive Messages • Processes has to receive a message if it sends message or execute a local event for two times consecutively. • Number of processes varied: 3, 5, 10, 15, ….50.

5. Number of Messages for S-K and VC implementation

6. Space requirement of S-K implementation

7. Conclusion • Vector clock is not scalable • S-K algorithm needs significant small messages than vector clock algorithm • The saving of S-K method increases with number of processes • For very small number of processes, Vector clock needs small number of messages than S-K algorithm. • S-K algorithm needs 3 times space than vector clock algorithm

8. Future Works • Here we measured the performance of S-K algorithm for ring topology. Research should be done for other topologies, such as, mesh or completely connected topology • Research should be conducted on how program behavior affect the performance of S-K method. • Find out the situation when Vector Clock algorithm may outperform S-K method.

9. Questions??