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Adam Fuchs updated ACCUMULO-550: -------------------------------- Summary: Collocate rfile index entries within file (was: Colocate rfile index entries within file) > Collocate rfile index entries within file > ----------------------------------------- > > Key: ACCUMULO-550 > URL: https://issues.apache.org/jira/browse/ACCUMULO-550 > Project: Accumulo > Issue Type: Improvement > Components: tserver > Reporter: Keith Turner > Assignee: Keith Turner > Fix For: 1.5.0, 1.4.1 > > > Before multi-level indexes were introduced, when an an rfile was written its > entire index was held in memory and written out then the file was closed. > With the introduction of multilevel index each index block is written when it > fills up as the file is being written. This was done to handle the case > where the index may not fit into memory. This leads to index blocks being > sprinkled through the file. So any operation that iterates over the entire > index can be slow because it turns into a lot of random accesses. > One possible solution is to buffer lots of index blocks up to some some > threshold and write out alot of index blocks at once. This would make a scan > of the index much faster as it would turn into a set of sequential reads of > large chunks of data. > Could buffer all block at a particular level and write them out when the > parent index block fills up. -- 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