[HBASE-7381] Lightweight data transfer for Class Result

• Type: Improvement
• Status: Closed
• Priority: Trivial
• Resolution: Fixed
• Fix Version/s: 0.94.4
• Component/s: Client
• Hadoop Flags: Reviewed
• Assignee: Cheng Hao
• Reporter: Cheng Hao
• Created: 18/Dec/12 05:14
• Updated: 02/May/13 02:29
• Resolved: 19/Dec/12 06:54

Description

Currently,the data transferring between 2 Result objects in the same process, will cause additional/unnecessary data parsing & copying; as we have to do that via "Writables.copyWritable(result1, result2)", which internally is serialization, data copying, and de-serialization.

The use case are quite common when integrated with Hadoop job running;
The protocol org.apache.hadoop.mapred.RecordReader defined in Hadoop, provides 3 interfaces:
1) K createKey();
2) V createValue();
3) boolean next(K key, V value) throws IOException;

In the 3rd method implementation, most likely requires the value (should be Result object) to be filled, with the Result object from HBase.

Issue Links

• is depended upon by: HIVE-3823 Performance issue while retrieving the Result objects in HiveHBaseTableInputFormat