Hi,Jouni: I agree. By the way, [2] also points out the a more intelligent time out value between neighor nodes will improve transaction latency and could be exploited to choose another better node timely. So periodical recovery or keepalive message facilitates the computation of the time out value.
> Hi, > > The RELOAD draft specifies in chapter 12 a modified version of the > Chordalgorithm. It seems to me that this modified Chord algorithm uses > reactive recovery from node failures instead of periodic recovery, > whichis used by the original Chord algorithm as specified in [1]. > In reactive > recovery, a node reacts to the loss of a node in its neighborhood > set by > sending a copy of it neighbor table to all nodes in the neighborhood > set. Periodic recovery, in contrast, takes place independently of > changes in the neighborhood set. In periodic recovery, a node > periodically shares its neighborhood set with each of the members of > that set. > > It has been shown in [2] that reactive recovery is only efficient > at low > churn rates. With moderate and high churn rates, periodic recovery > usesless bandwidth and the resulting lower contention of the > network leads > to lower latencies. My concern is that because it uses reactive > recovery, the performance of RELOAD's Chord algorithm may degrade > undermoderate and high churn rates. > > As an example, the first version of the Bamboo DHT algorithm used > reactive recovery. As a consequence, Bamboo suffered a performance > degradation under churn. To solve this issue, Bamboo was modified > to use > periodic recovery from node failures. > > Any comments? > > [1] I. Stoica, R. Morris, D. Karger, M. F. Kaashoek, and H. > Balakrishnan. Chord: A scalable peer-to-peer lookup service for > Internetapplications. Technical Report TR-819, MIT, March 2001 > [2] S. Rhea, D. Geels, T. Roscoe, and J. Kubiatowicz. Handling > churn in > a DHT. In Proc. of USENIX Technical Conference, June 2004 > > Regards, > Jouni > _______________________________________________ > P2PSIP mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/p2psip > _______________________________________________ P2PSIP mailing list [email protected] https://www.ietf.org/mailman/listinfo/p2psip
