Andy Pernsteiner created DRILL-3270:
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Summary: Modify HbaseGroupScan to allow multiple fragments per region
Key: DRILL-3270
URL: https://issues.apache.org/jira/browse/DRILL-3270
Project: Apache Drill
Issue Type: Improvement
Components: Query Planning & Optimization, Storage - HBase
Affects Versions: 1.0.0
Reporter: Andy Pernsteiner
Assignee: Jinfeng Ni
Priority: Minor
When performing a full HBASE or MapR-DB table scan using drill, it is observed within the
resulting query profile that only one minor fragment is assigned per region, regardless of
the size of the region. In the case of extremely large regions, especially if there are regions
of mismatching sizes, this can result in poor performance and a low degree of parallelism.
One possible option (mentioned by sphillips) is to lazily compute the splits by assuming that
the keys within a given region were evenly distributed (not perfect, but better than nothing),
and perhaps have a 'max-frags-per-region' setting.
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