Stable Release 0.94.2.200

Tested in a 2 Dual Core Ubuntu Laptop

483,972,182 Rows * 7 Fields
Matching *|*|*|*|*|*|*
Grouping Done.
time take 7603 milli seconds

Machine
Ubuntu Release 12.04 (precise) 64-bit
processor Intel® Core™ i5-3210M CPU @ 2.50GHz × 4
Standalone HBase with HMaster : export HBASE_HEAPSIZE=4096
JVM HBASE_OPTS="-server -Xms1024m -XX:+UseConcMarkSweepGC"