Gruppwebben som samarbetsyta stängs 31 december 2026. Du som administratör behöver nu exportera gruppens innehåll och/eller radera gruppen.
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Mer information hittar du i nyheten: Gruppwebben och Social stänger hösten 2026. Stöd och instruktioner för hur du exporterar en gruppwebb finns i: Gruppwebben som samarbetsyta stängs hösten 2026.
Highly Available Lock Service
Chubby and Zookeeper are examples of higly available lock services and are used to coordinate services in cloud environments. Your task is to build a similar lock service and provide a consistent service that survives even if some nodes crash or are cut of from the network. In order to build the system you should know that Paxos is not only a Greek island and that eventual perfect failure detectors are a EMDC students best friend.
You can choose to implement the system using any programming language but you should implement your solution from scratch and not use a middlelayer that solves the hard problems. You should also do performance messurements and show the performance under normal conditions as well as when things crash.
Here are some papers that will help you on your way:
- L. Lamport, "Paxos Made Simple", ACM SIGACT News (Distributed Computing Column) 32, 4 (Whole Number 121, December 2001) 51-58
- F. Schneider, "Implementing fault-tolerant services using the state machine approach: A tutorial", ACM Computing Surveys (CSUR), vol. 22, no. 4, pp. 299{319, 1990.
- David Mazières, "Paxos Made Practical"
- Mike Burrows. "Chubby distributed lock service". In Proceedings of the 7th Symposium on Operating Systems Design and Implementation, Seattle, WA, November 2006.
- Patrick Hunt, Mahadev Konar, Flavio P. Junqueira and Benjamin Reed, "ZooKeeper: Wait-free coordination for Internet-scale systems " In Proceedings of the 2010 USENIX conference on USENIX annual technical conference (USENIXATC’10). USENIX Association, Berkeley, CA, USA, 11-11, (2010)
Supervised by: Johan Montelius