diff --git a/utils/nio/src/test/java/org/onlab/nio/IOLoopTestClient.java b/utils/nio/src/test/java/org/onlab/nio/IOLoopTestClient.java
index 6f6bd6d..dba0b18 100644
--- a/utils/nio/src/test/java/org/onlab/nio/IOLoopTestClient.java
+++ b/utils/nio/src/test/java/org/onlab/nio/IOLoopTestClient.java
@@ -25,6 +25,7 @@
 
 import static java.lang.String.format;
 import static java.lang.System.currentTimeMillis;
+import static java.lang.System.nanoTime;
 import static java.lang.System.out;
 import static org.onlab.nio.IOLoopTestServer.PORT;
 import static org.onlab.util.Tools.delay;
@@ -183,7 +184,7 @@
      */
     public void report() {
         DecimalFormat f = new DecimalFormat("#,##0");
-        out.println(format("Client: %s messages; %s bytes; %s mps; %s Mbs; %s ms latency",
+        out.println(format("Client: %s messages; %s bytes; %s mps; %s Mbs; %s ns latency",
                            f.format(messages.total()), f.format(bytes.total()),
                            f.format(messages.throughput()),
                            f.format(bytes.throughput() / (1024 * msgLength)),
@@ -231,7 +232,7 @@
                                        MessageStream<TestMessage> stream) {
             for (TestMessage message : messages) {
                 // TODO: summarize latency data better
-                latencyTotal += currentTimeMillis() - message.requestorTime();
+                latencyTotal += nanoTime() - message.requestorTime();
                 latencyCount++;
             }
             worker.release(messages.size());
@@ -252,7 +253,7 @@
      */
     private class Worker implements Runnable {
 
-        private static final int BATCH_SIZE = 1000;
+        private static final int BATCH_SIZE = 50;
         private static final int PERMITS = 2 * BATCH_SIZE;
 
         private TestMessageStream stream;
@@ -295,8 +296,7 @@
             // Build a batch of messages
             List<TestMessage> batch = Lists.newArrayListWithCapacity(size);
             for (int i = 0; i < size; i++) {
-                batch.add(new TestMessage(msgLength, currentTimeMillis(), 0,
-                                          stream.padding()));
+                batch.add(new TestMessage(msgLength, nanoTime(), 0, stream.padding()));
             }
             acquire(size);
             stream.write(batch);