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dhruba borthakur commented on HBASE-1364: ----------------------------------------- -- Connect to me at http://www.facebook.com/dhruba > [performance] Distributed splitting of regionserver commit logs > --------------------------------------------------------------- > > Key: HBASE-1364 > URL: https://issues.apache.org/jira/browse/HBASE-1364 > Project: HBase > Issue Type: Improvement > Components: coprocessors > Reporter: stack > Assignee: Prakash Khemani > Priority: Critical > Fix For: 0.92.0 > > Attachments: HBASE-1364.patch > > Time Spent: 8h > Remaining Estimate: 0h > > HBASE-1008 has some improvements to our log splitting on regionserver crash; > but it needs to run even faster. > (Below is from HBASE-1008) > In bigtable paper, the split is distributed. If we're going to have 1000 > logs, we need to distribute or at least multithread the splitting. > 1. As is, regions starting up expect to find one reconstruction log only. > Need to make it so pick up a bunch of edit logs and it should be fine that > logs are elsewhere in hdfs in an output directory written by all split > participants whether multithreaded or a mapreduce-like distributed process > (Lets write our distributed sort first as a MR so we learn whats involved; > distributed sort, as much as possible should use MR framework pieces). On > startup, regions go to this directory and pick up the files written by split > participants deleting and clearing the dir when all have been read in. Making > it so can take multiple logs for input, can also make the split process more > robust rather than current tenuous process which loses all edits if it > doesn't make it to the end without error. > 2. Each column family rereads the reconstruction log to find its edits. Need > to fix that. Split can sort the edits by column family so store only reads > its edits. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira