diff --git a/runners/google-cloud-dataflow-java/src/main/java/org/apache/beam/runners/dataflow/options/DataflowPipelineDebugOptions.java b/runners/google-cloud-dataflow-java/src/main/java/org/apache/beam/runners/dataflow/options/DataflowPipelineDebugOptions.java
index 30496dec2965..3f6c47ece68a 100644
--- a/runners/google-cloud-dataflow-java/src/main/java/org/apache/beam/runners/dataflow/options/DataflowPipelineDebugOptions.java
+++ b/runners/google-cloud-dataflow-java/src/main/java/org/apache/beam/runners/dataflow/options/DataflowPipelineDebugOptions.java
@@ -218,11 +218,12 @@ public Dataflow create(PipelineOptions options) {
 
   /** The max amount of time an UnboundedReader is consumed before checkpointing. */
   @Description(
-      "The max amount of time before an UnboundedReader is consumed before checkpointing, in seconds.")
-  @Default.Integer(10)
-  Integer getUnboundedReaderMaxReadTimeSec();
+      "The max amount of time before an UnboundedReader is consumed before checkpointing, "
+          + "in seconds. Duration can be set to fractions of seconds. ")
+  @Default.Double(10.0)
+  double getUnboundedReaderMaxReadTimeSec();
 
-  void setUnboundedReaderMaxReadTimeSec(Integer value);
+  void setUnboundedReaderMaxReadTimeSec(double value);
 
   /** The max elements read from an UnboundedReader before checkpointing. */
   @Description("The max elements read from an UnboundedReader before checkpointing. ")
diff --git a/runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSources.java b/runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSources.java
index 8c086016ee95..a8e358f19e07 100644
--- a/runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSources.java
+++ b/runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSources.java
@@ -798,7 +798,9 @@ private UnboundedReaderIterator(
       DataflowPipelineDebugOptions debugOptions = options.as(DataflowPipelineDebugOptions.class);
       this.endTime =
           Instant.now()
-              .plus(Duration.standardSeconds(debugOptions.getUnboundedReaderMaxReadTimeSec()));
+              .plus(
+                  Duration.millis(
+                      (long) (debugOptions.getUnboundedReaderMaxReadTimeSec() * 1000L)));
       this.maxElems = debugOptions.getUnboundedReaderMaxElements();
       this.backoffFactory =
           FluentBackoff.DEFAULT
diff --git a/runners/google-cloud-dataflow-java/worker/src/test/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSourcesTest.java b/runners/google-cloud-dataflow-java/worker/src/test/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSourcesTest.java
index d451ec093f77..261567930fe6 100644
--- a/runners/google-cloud-dataflow-java/worker/src/test/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSourcesTest.java
+++ b/runners/google-cloud-dataflow-java/worker/src/test/java/org/apache/beam/runners/dataflow/worker/WorkerCustomSourcesTest.java
@@ -598,6 +598,7 @@ public void testReadUnboundedReader() throws Exception {
     int maxElements = 10;
     DataflowPipelineDebugOptions debugOptions = options.as(DataflowPipelineDebugOptions.class);
     debugOptions.setUnboundedReaderMaxElements(maxElements);
+    debugOptions.setUnboundedReaderMaxReadTimeSec(10);
 
     ByteString state = ByteString.EMPTY;
     for (int i = 0; i < 10 * maxElements;
@@ -645,10 +646,10 @@ public void testReadUnboundedReader() throws Exception {
         numReadOnThisIteration++;
       }
       Instant afterReading = Instant.now();
-      long maxReadSec = debugOptions.getUnboundedReaderMaxReadTimeSec();
+      double maxReadSec = debugOptions.getUnboundedReaderMaxReadTimeSec();
       assertThat(
-          new Duration(beforeReading, afterReading).getStandardSeconds(),
-          lessThanOrEqualTo(maxReadSec + 1));
+          new Duration(beforeReading, afterReading).getMillis(),
+          lessThanOrEqualTo((long) ((maxReadSec + 1) * 1000L)));
       assertThat(
           numReadOnThisIteration, lessThanOrEqualTo(debugOptions.getUnboundedReaderMaxElements()));