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Lars Hofhansl commented on HBASE-9272: -------------------------------------- Yeah, that was the one where I convinced Stack that we do not need this. :) > A simple parallel, unordered scanner > ------------------------------------ > > Key: HBASE-9272 > URL: https://issues.apache.org/jira/browse/HBASE-9272 > Project: HBase > Issue Type: New Feature > Reporter: Lars Hofhansl > Priority: Minor > Attachments: ParallelClientScanner.java > > > The contract of ClientScanner is to return rows in sort order. That limits > the order in which region can be scanned. > I propose a simple ParallelScanner that does not have this requirement and > queries regions in parallel, return whatever gets returned first. > This is generally useful for scans that filter a lot of data on the server, > or in cases where the client can very quickly react to the returned data. > I have a simple prototype (doesn't do error handling right, and might be a > bit heavy on the synchronization side - it used a BlockingQueue to hand data > between the client using the scanner and the threads doing the scanning, it > also could potentially starve some scanners long enugh to time out at the > server). > On the plus side, it's only a 130 lines of code. :) -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira