Lightweight log management algorithm for removing logged messages of sender processes with little overhead

• Authors: Jinho Ahn
• Venue: WSEAS Transactions on Computers
• Year: 2008

Sender-based message logging allows each message to be logged in the volatile storage of its corresponding sender. This behavior avoids logging messages on the stable storage synchronously and results in lower failure-free overhead than receiver-based message logging. However, in the first approach, each process should keep in its limited volatile storage the log information of its sent messages for recovering their receivers. In this paper, we propose a 2-step algorithm to efficiently remove logged messages from the volatile storage while ensuring the consistent recovery of the system in case of process failures. As the first step, the algorithm eliminates useless log information in the volatile storage with no extra message and forced checkpoint. But, even if the step has been performed, the more empty buffer space for logging messages in future may be required. In this case, the second step forces the useful log information to become useless by maintaining a vector to record the size of the information for every other process. This behavior incurs fewer additional messages and forced checkpoints than existing algorithms. Experimental results verify that our algorithm significantly performs better than the traditional one with respect to the garbage collection overhead.