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dhruba borthakur commented on ZOOKEEPER-1001: --------------------------------------------- On a related question: is the writing of a ledger entry atomic (for a single bookie)? For example, if an application writes a ledger entry to a certain bookie and a concurrent reader tries to read that entry (even if that entry is not committed to all bookies), is it possible that only a part of that ledger entry is visible to the reader? > 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 > Attachments: zk-1001-design-doc.pdf, zk-1001-design-doc.pdf > > > 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