diff --git a/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterWithThreads.java b/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterWithThreads.java
index 004e746..2a6f344 100644
--- a/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterWithThreads.java
+++ b/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterWithThreads.java
@@ -23,6 +23,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
+import java.util.Random;
 
 import org.apache.lucene.analysis.MockAnalyzer;
 import org.apache.lucene.document.Document;
@@ -532,9 +533,10 @@ public class TestIndexWriterWithThreads extends LuceneTestCase {
       threads[threadID] = new Thread() {
           @Override
           public void run() {
+            Random random = new Random(random().nextLong());
             for(int iter=0;iter<iters && !failed.get();iter++) {
               //final int x = random().nextInt(5);
-              final int x = random().nextInt(3);
+              final int x = random.nextInt(3);
               try {
                 switch(x) {
                 case 0:
@@ -547,7 +549,7 @@ public class TestIndexWriterWithThreads extends LuceneTestCase {
                     if (VERBOSE) {
                       System.out.println("TEST: " + Thread.currentThread().getName() + ": rollback done; now open new writer");
                     }
-                    writerRef.set(new IndexWriter(d, newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))));
+                    writerRef.set(new IndexWriter(d, newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random))));
                   } finally {
                     rollbackLock.unlock();
                   }
@@ -558,7 +560,7 @@ public class TestIndexWriterWithThreads extends LuceneTestCase {
                     System.out.println("\nTEST: " + Thread.currentThread().getName() + ": now commit");
                   }
                   try {
-                    if (random().nextBoolean()) {
+                    if (random.nextBoolean()) {
                       writerRef.get().prepareCommit();
                     }
                     writerRef.get().commit();