Re: [newb] cross-WAN ZK use?

[Flavio Junqueira]

Hi David, I'm not sure I understand your question. When you say "relax latency requirements" and "giving up performance", do you mean that you don't mind having higher latency and lower throughput? If so, then I think you can get it straight away with ZooKeeper. Depending on how many data centers you have, and how far apart they ar, you may consider using a different quorum configuration using this mechanism: http://hadoop.apache.org/zookeeper/docs/r3.3.2/zookeeperHierarchicalQuorums.html http://hadoop.apache.org/zookeeper/docs/r3.3.2/zookeeperAdmin.html -Flavio On Dec 5, 2010, at 6:47 PM, David Carmean wrote: Greetings, I've been reading about ZK (and Hedwig) off and on for a few days, and I have a small application where ZK might be useful, but there is some doubt. My present app has very low performance requirements; I'm looking to maintain no more than a couple of thousand tiny znodes as configuration items and coordination bits for a monitoring application.  I'm experimenting with cross-site failover capability for various tiers of this application. One of the requirements, however, is to be robust against a complete outage of any one datacenter (client has been burned by such an outage recently...) Is it possible to turn some knobs that would relax the latency requirements in the ensemble voting process in return for giving up performance?  I really don't need more than a few tens of writes per second for this app. Thanks. flavio junqueira   research scientist   f...@yahoo-inc.com direct +34 93-183-8828   avinguda diagonal 177, 8th floor, barcelona, 08018, es phone (408) 349 3300    fax (408) 349 3301