DRILL-7761: Drill fails with OOM for the case of large filter conditions

Author: vvysotskyi

exec/java-exec/src/main/java/org/apache/drill/exec/store/parquet/FilePushDownFilter.java

@@ -136,7 +136,9 @@ protected void doOnMatch(RelOptRuleCall call, FilterPrel filter, ProjectPrel pro
 
     // get a conjunctions of the filter condition. For each conjunction, if it refers to ITEM or FLATTEN expression
     // then we could not pushed down. Otherwise, it's qualified to be pushed down.
-    final List<RexNode> predList = RelOptUtil.conjunctions(RexUtil.toCnf(filter.getCluster().getRexBuilder(), condition));
+    // Limits the number of nodes that can be created out of the conversion to avoid
+    // exponential growth of nodes count and further OOM
+    final List<RexNode> predList = RelOptUtil.conjunctions(RexUtil.toCnf(filter.getCluster().getRexBuilder(), 100, condition));
 
     final List<RexNode> qualifiedPredList = new ArrayList<>();
 

exec/java-exec/src/test/java/org/apache/drill/exec/store/parquet/TestParquetFilterPushDown.java

@@ -446,6 +446,28 @@ public void testParquetFilterPDOptionsThreshold() throws Exception {
     }
   }
 
+  @Test
+  public void testParquetFilterPDWithLargeCondition() throws Exception {
+    test("SELECT * FROM (SELECT n.n_name AS name, n.n_nationkey AS nationkey, " +
+        "cast(n.n_regionkey AS FLOAT) AS regionkey FROM cp.`/tpch/nation.parquet` n) " +
+        "WHERE ((name = 'A' AND ((regionkey >= 0.0 AND regionkey <= 120.0 AND nationkey = 0.005))) " +
+        "OR (name = 'B' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'C' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'D' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'E' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'F' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'G' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'I' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'J' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'K' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'L' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'M' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'N' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'O' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'P' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))) " +
+        "OR (name = 'Q' AND ((regionkey >= 0.0  AND regionkey <= 120.0  AND nationkey = 0.005))))");
+  }
+
   @Test
   public void testDatePredicateAgainstCorruptedDateCol() throws Exception {
     // Table dateTblCorrupted is created by CTAS in drill 1.8.0. Per DRILL-4203, the date column is shifted by some value.