diff --git a/processing/src/main/java/io/druid/segment/incremental/OnheapIncrementalIndex.java b/processing/src/main/java/io/druid/segment/incremental/OnheapIncrementalIndex.java
index cbe9ba48bc9..5404aa07147 100644
--- a/processing/src/main/java/io/druid/segment/incremental/OnheapIncrementalIndex.java
+++ b/processing/src/main/java/io/druid/segment/incremental/OnheapIncrementalIndex.java
@@ -77,7 +77,7 @@ public class OnheapIncrementalIndex extends IncrementalIndex<Aggregator>
   {
     super(incrementalIndexSchema, deserializeComplexMetrics, reportParseExceptions, concurrentEventAdd);
     this.maxRowCount = maxRowCount;
-    this.maxBytesInMemory = maxBytesInMemory == 0 ? -1 : maxBytesInMemory;
+    this.maxBytesInMemory = maxBytesInMemory == 0 ? Long.MAX_VALUE : maxBytesInMemory;
     this.facts = incrementalIndexSchema.isRollup() ? new RollupFactsHolder(sortFacts, dimsComparator(), getDimensions())
                                                    : new PlainFactsHolder(sortFacts);
     maxBytesPerRowForAggregators = getMaxBytesPerRowForAggregators(incrementalIndexSchema);
@@ -170,7 +170,7 @@ public class OnheapIncrementalIndex extends IncrementalIndex<Aggregator>
       concurrentSet(rowIndex, aggs);
 
       // Last ditch sanity checks
-      if ((numEntries.get() >= maxRowCount || (maxBytesInMemory > 0 && sizeInBytes.get() >= maxBytesInMemory))
+      if ((numEntries.get() >= maxRowCount || sizeInBytes.get() >= maxBytesInMemory)
           && facts.getPriorIndex(key) == IncrementalIndexRow.EMPTY_ROW_INDEX
           && !skipMaxRowsInMemoryCheck) {
         throw new IndexSizeExceededException(
diff --git a/server/src/main/java/io/druid/segment/indexing/TuningConfigs.java b/server/src/main/java/io/druid/segment/indexing/TuningConfigs.java
index 571005f4370..bc4df16d1c1 100644
--- a/server/src/main/java/io/druid/segment/indexing/TuningConfigs.java
+++ b/server/src/main/java/io/druid/segment/indexing/TuningConfigs.java
@@ -29,6 +29,12 @@ public class TuningConfigs
     // In the main tuningConfig class constructor, we set the maxBytes to 0 if null to avoid setting
     // maxBytes to max jvm memory of the process that starts first. Instead we set the default based on
     // the actual task node's jvm memory.
-    return maxBytesInMemory == 0 ? TuningConfig.DEFAULT_MAX_BYTES_IN_MEMORY : maxBytesInMemory;
+    long newMaxBytesInMemory = maxBytesInMemory;
+    if (maxBytesInMemory == 0) {
+      newMaxBytesInMemory = TuningConfig.DEFAULT_MAX_BYTES_IN_MEMORY;
+    } else if (maxBytesInMemory < 0) {
+      newMaxBytesInMemory = Long.MAX_VALUE;
+    }
+    return newMaxBytesInMemory;
   }
 }
diff --git a/server/src/main/java/io/druid/segment/realtime/appenderator/AppenderatorImpl.java b/server/src/main/java/io/druid/segment/realtime/appenderator/AppenderatorImpl.java
index e5c2954f2d6..a9eb40611d0 100644
--- a/server/src/main/java/io/druid/segment/realtime/appenderator/AppenderatorImpl.java
+++ b/server/src/main/java/io/druid/segment/realtime/appenderator/AppenderatorImpl.java
@@ -126,6 +126,7 @@ public class AppenderatorImpl implements Appenderator
   private final VersionedIntervalTimeline<String, Sink> sinkTimeline = new VersionedIntervalTimeline<>(
       String.CASE_INSENSITIVE_ORDER
   );
+  private final long maxBytesTuningConfig;
 
   private final QuerySegmentWalker texasRanger;
   // This variable updated in add(), persist(), and drop()
@@ -182,7 +183,7 @@ public class AppenderatorImpl implements Appenderator
         Preconditions.checkNotNull(cache, "cache"),
         cacheConfig
     );
-
+    maxBytesTuningConfig = TuningConfigs.getMaxBytesInMemoryOrDefault(tuningConfig.getMaxBytesInMemory());
     log.info("Created Appenderator for dataSource[%s].", schema.getDataSource());
   }
 
@@ -260,7 +261,7 @@ public class AppenderatorImpl implements Appenderator
     if (System.currentTimeMillis() > nextFlush) {
       persist = true;
       persistReasons.add(StringUtils.format(
-          " current time[%d] is greater than nextFlush[%d],",
+          "current time[%d] is greater than nextFlush[%d]",
           System.currentTimeMillis(),
           nextFlush
       ));
@@ -268,19 +269,17 @@ public class AppenderatorImpl implements Appenderator
     if (rowsCurrentlyInMemory.get() >= tuningConfig.getMaxRowsInMemory()) {
       persist = true;
       persistReasons.add(StringUtils.format(
-          " rowsCurrentlyInMemory[%d] is greater than maxRowsInMemory[%d],",
+          "rowsCurrentlyInMemory[%d] is greater than maxRowsInMemory[%d]",
           rowsCurrentlyInMemory.get(),
           tuningConfig.getMaxRowsInMemory()
       ));
     }
-    if (tuningConfig.getMaxBytesInMemory() > 0
-        && bytesCurrentlyInMemory.get()
-           >= TuningConfigs.getMaxBytesInMemoryOrDefault(tuningConfig.getMaxBytesInMemory())) {
+    if (bytesCurrentlyInMemory.get() >= maxBytesTuningConfig) {
       persist = true;
       persistReasons.add(StringUtils.format(
-          " bytesCurrentlyInMemory[%d] is greater than maxBytesInMemory[%d]",
+          "bytesCurrentlyInMemory[%d] is greater than maxBytesInMemory[%d]",
           bytesCurrentlyInMemory.get(),
-          TuningConfigs.getMaxBytesInMemoryOrDefault(tuningConfig.getMaxBytesInMemory())
+          maxBytesTuningConfig
       ));
     }
     if (persist) {
@@ -354,7 +353,7 @@ public class AppenderatorImpl implements Appenderator
           identifier.getShardSpec(),
           identifier.getVersion(),
           tuningConfig.getMaxRowsInMemory(),
-          TuningConfigs.getMaxBytesInMemoryOrDefault(tuningConfig.getMaxBytesInMemory()),
+          maxBytesTuningConfig,
           tuningConfig.isReportParseExceptions(),
           null
       );
@@ -1026,7 +1025,7 @@ public class AppenderatorImpl implements Appenderator
             identifier.getShardSpec(),
             identifier.getVersion(),
             tuningConfig.getMaxRowsInMemory(),
-            TuningConfigs.getMaxBytesInMemoryOrDefault(tuningConfig.getMaxBytesInMemory()),
+            maxBytesTuningConfig,
             tuningConfig.isReportParseExceptions(),
             null,
             hydrants