[HBASE-9807] block encoder unnecessarily copies the key for each reseek

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.98.0, 0.94.13, 0.96.1
• Hadoop Flags: Reviewed
• Assignee: Lars Hofhansl
• Reporter: Lars Hofhansl
• Created: 20/Oct/13 07:41
• Updated: 08/Nov/13 04:03
• Resolved: 25/Oct/13 20:59

Description

In HFileReaderV2.AbstractScannerV2.reseekTo(...) we have this:

        ByteBuffer bb = getKey();
        compared = reader.getComparator().compare(key, offset,
            length, bb.array(), bb.arrayOffset(), bb.limit());

getKey() creates two ByteBuffers in ScannerV2 and makes a deep copy of the key in EncodedScannerV2.