diff --git a/gradle/knn.gradle b/gradle/knn.gradle
index d9c95628..65000e07 100644
--- a/gradle/knn.gradle
+++ b/gradle/knn.gradle
@@ -22,10 +22,10 @@ def highDimDataSets = [
 ]
 
 
-// def luceneDir = (String) findProperty("external.lucene.repo") + '/lucene'
-def luceneDir = "/l/trunk/lucene"
-// def luceneVersion = (String) findProperty("lucene.version")
-def luceneVersion = "11.0.0"
+def luceneDir = (String) findProperty("external.lucene.repo") + '/lucene'
+//def luceneDir = "/l/trunk/lucene"
+def luceneVersion = (String) findProperty("lucene.version")
+//def luceneVersion = "11.0.0"
 def luceneFT = fileTree(dir: luceneDir, include: "**/*$luceneVersion-SNAPSHOT.jar")
 
 task compileKnn (type: JavaCompile) {
diff --git a/src/main/build.gradle b/src/main/build.gradle
index 6771571c..2bdc5d0e 100644
--- a/src/main/build.gradle
+++ b/src/main/build.gradle
@@ -3,7 +3,10 @@ plugins {
 }
 
 sourceSets {
-  main.java.srcDirs = ['knn', 'perf']
+  main.java {
+    srcDir '.'
+    include 'perf', 'knn'
+  }
 }
 
 def luceneDir = (String) findProperty("external.lucene.repo") + '/lucene'
diff --git a/src/main/knn/KnnIndexerMain.java b/src/main/knn/KnnIndexerMain.java
index 3e136b74..9d634f9a 100644
--- a/src/main/knn/KnnIndexerMain.java
+++ b/src/main/knn/KnnIndexerMain.java
@@ -58,7 +58,7 @@ public String toString() {
         '}';
   }
 
-  public static void main(String[] args) throws IOException {
+  public static void main(String[] args) throws Exception {
     KnnIndexerMain inputs = new KnnIndexerMain();
 
     try {
@@ -102,6 +102,7 @@ public static void main(String[] args) throws IOException {
 
     new KnnIndexer(inputs.docVectorsPath, inputs.indexPath,
                    KnnGraphTester.getCodec(inputs.maxConn, inputs.beamWidth, exec, numMergeWorker, quantize, quantizeBits, quantizeCompress),
+                   numMergeThread,
                    inputs.vectorEncoding,
                    inputs.dimension, inputs.similarityFunction, inputs.numDocs, inputs.docStartIndex, inputs.quiet,
                    inputs.parentJoin, inputs.parentJoinMetaFile).createIndex();