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Zhihong Yu commented on HBASE-5877: ----------------------------------- {code} + final Set<String> updateHistory = new HashSet<String>(100); {code} Since updateCachedLocations() is used to handle exception, the presizing above may not be needed. {code} + this(server, rsServices, regionInfo, abort, zk, versionOfClosingNode, eventType, null); + } + + protected CloseRegionHandler(final Server server, {code} The indentation of CloseRegionHandler() above is off. {code} + // This map will contains all the regions that we closed for a move. + // We add the time it was moved as we don't want to keep a too old information {code} 'will contains' -> 'will contain'. 'keep a too old' -> 'keep too old'. This is a very useful feature. Good work, N. > When a query fails because the region has moved, let the regionserver return > the new address to the client > ---------------------------------------------------------------------------------------------------------- > > Key: HBASE-5877 > URL: https://issues.apache.org/jira/browse/HBASE-5877 > Project: HBase > Issue Type: Improvement > Components: client, master, regionserver > Affects Versions: 0.96.0 > Reporter: nkeywal > Assignee: nkeywal > Priority: Minor > Fix For: 0.96.0 > > Attachments: 5877.v1.patch, 5877.v12.patch, 5877.v6.patch > > > This is mainly useful when we do a rolling restart. This will decrease the > load on the master and the network load. > Note that a region is not immediately opened after a close. So: > - it seems preferable to wait before retrying on the other server. An > optimisation would be to have an heuristic depending on when the region was > closed. > - during a rolling restart, the server moves the regions then stops. So we > may have failures when the server is stopped, and this patch won't help. > The implementation in the first patch does: > - on the region move, there is an added parameter on the regionserver#close > to say where we are sending the region > - the regionserver keeps a list of what was moved. Each entry is kept 100 > seconds. > - the regionserver sends a specific exception when it receives a query on a > moved region. This exception contains the new address. > - the client analyses the exeptions and update its cache accordingly... -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira