HBASE-26761 TestMobStoreScanner (testGetMassive) can OOME (#4204)

Change the timing of the test but not the objective by storing three large
MOB values into the row with three separate puts, each randomizing the
data. Increases running time of the testGetMassive case 2x but avoids OOME
in the test environment where the OOME was consistently reproductable.

Signed-off-by: Duo Zhang <[email protected]>
Signed-off-by: Pankaj Kumar <[email protected]>

Author: apurtell

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMobStoreScanner.java

@@ -166,8 +166,15 @@ public void testGetMassive() throws Exception {
     byte[] bigValue = new byte[25*1024*1024];
 
     Put put = new Put(row1);
+    Bytes.random(bigValue);
     put.addColumn(family, qf1, bigValue);
+    table.put(put);
+    put = new Put(row1);
+    Bytes.random(bigValue);
     put.addColumn(family, qf2, bigValue);
+    table.put(put);
+    put = new Put(row1);
+    Bytes.random(bigValue);
     put.addColumn(family, qf3, bigValue);
     table.put(put);