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Flavio Junqueira commented on ZOOKEEPER-1001: --------------------------------------------- The problem of reading uncommitted entries is that the uncommitted entries may never be committed, and it may lead to inconsistencies in the system. Say that the writer writes entry n+1 to a single bookie and crashes before it is able to commit it. A concurrent reader may end up reading n+1, and a later client that recovers the ledger may end up reading up to n only. This might lead to inconsistencies in some use cases, perhaps not yours. At the same time, your description sort of supports our preference for notifying outside bookkeeper. If your use case does not require it, then you may choose not to implement it. > Read from open ledger > --------------------- > > Key: ZOOKEEPER-1001 > URL: https://issues.apache.org/jira/browse/ZOOKEEPER-1001 > Project: ZooKeeper > Issue Type: New Feature > Components: contrib-bookkeeper > Reporter: Flavio Junqueira > > The BookKeeper client currently does not allow a client to read from an open > ledger. That is, if the creator of a ledger is still writing to it (and the > ledger is not closed), then an attempt to open the same ledger for reading > will execute the code to recover the ledger, assuming that the ledger has not > been correctly closed. > It seems that there are applications that do require the ability to read from > a ledger while it is being written to, and the main goal of this jira is to > discuss possible implementations of this feature. -- This message is automatically generated by JIRA. - For more information on JIRA, see: http://www.atlassian.com/software/jira