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Eric Owhadi commented on TRAFODION-1421: ---------------------------------------- Anoop, you are talking about "merging sorted streams": In what I was going to implement the stream seen by ESP or Master executor would not be multiple streams, but a single stream of unsorted data (not random data, but intermingle of multiple regions scanned in parallel data in a single stream. So for operators that needs sorted stream, that parallel scanner would not be appropriate. Hope this is still useful ? I guess it is since you would get multi-threading parallelism on top of ESP (multi process parallelism)? > Implement parallel Scanner primitive > ------------------------------------ > > Key: TRAFODION-1421 > URL: https://issues.apache.org/jira/browse/TRAFODION-1421 > Project: Apache Trafodion > Issue Type: Improvement > Components: sql-cmp, sql-exe > Reporter: Eric Owhadi > Assignee: Eric Owhadi > Labels: performance > Fix For: 2.0-incubating > > > ClientScanner API is serial, to conserve key ordering. However, many > operators don't care about ordering and would rather get the scan result > fast, regardless of order. This JIRA is about providing a parallel scanner, > that would take care of splitting the work between all region servers evenly > if possible. HBase had a parallel scanner in the pipe for quite some time > HBAse-9272, but the work is stalled since october 2013. However, looking at > the available code, look like a big part can be leveraged without requiring > an HBase custom build. -- This message was sent by Atlassian JIRA (v6.3.4#6332)