diff --git a/flink/v1.18/flink/src/main/java/org/apache/iceberg/flink/source/reader/IcebergSourceSplitReader.java b/flink/v1.18/flink/src/main/java/org/apache/iceberg/flink/source/reader/IcebergSourceSplitReader.java
index 29b18bd41bf6..2b6ce2c1470e 100644
--- a/flink/v1.18/flink/src/main/java/org/apache/iceberg/flink/source/reader/IcebergSourceSplitReader.java
+++ b/flink/v1.18/flink/src/main/java/org/apache/iceberg/flink/source/reader/IcebergSourceSplitReader.java
@@ -111,7 +111,7 @@ public RecordsWithSplitIds<RecordAndPosition<T>> fetch() throws IOException {
               wakeUp.wait(1000);
             } catch (InterruptedException e) {
               Thread.currentThread().interrupt();
-              throw new RuntimeException("Interrupted while blocked on reading.", e);
+              throw new RuntimeException("Interrupted while paused due to watermark alignment.", e);
             }
           }
         }
@@ -149,6 +149,12 @@ public void handleSplitsChanges(SplitsChange<IcebergSourceSplit> splitsChange) {
     metrics.incrementAssignedBytes(calculateBytes(splitsChange));
   }
 
+  /**
+   * WakeUp is called by Flink to unblock a reader blocked in {@link #fetch()} before calling {@link
+   * #handleSplitsChanges(SplitsChange)} or {@link #pauseOrResumeSplits(Collection, Collection)} to
+   * update the splits or splits state. After {@link #wakeUp()} the specific method will be called
+   * before calling the {@link #fetch()} again.
+   */
   @Override
   public void wakeUp() {
     LOG.info("WakeUp reader {}", indexOfSubtask);
diff --git a/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/TestIcebergSourceWithWatermarkExtractor.java b/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/TestIcebergSourceWithWatermarkExtractor.java
index 09dda67345d8..7aae59ca9d60 100644
--- a/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/TestIcebergSourceWithWatermarkExtractor.java
+++ b/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/TestIcebergSourceWithWatermarkExtractor.java
@@ -381,7 +381,7 @@ protected IcebergSource<RowData> source() {
         .project(TestFixtures.TS_SCHEMA)
         .splitSize(100L)
         .streaming(true)
-        .monitorInterval(Duration.ofMillis(100))
+        .monitorInterval(Duration.ofMillis(10))
         .streamingStartingStrategy(StreamingStartingStrategy.TABLE_SCAN_THEN_INCREMENTAL)
         // Read in single row batches, to have more batches for testing
         .flinkConfig(new Configuration().set(SOURCE_READER_FETCH_BATCH_RECORD_COUNT, 1))
diff --git a/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/reader/TestIcebergSourceSplitReader.java b/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/reader/TestIcebergSourceSplitReader.java
index 1d05661159e1..9e0f60da3aaa 100644
--- a/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/reader/TestIcebergSourceSplitReader.java
+++ b/flink/v1.18/flink/src/test/java/org/apache/iceberg/flink/source/reader/TestIcebergSourceSplitReader.java
@@ -136,7 +136,10 @@ public void testWakeup() throws Exception {
 
     // Wakeup the reading of the split, and check the result size
     reader.wakeUp();
-    Awaitility.await().atMost(2, TimeUnit.SECONDS).until(() -> gotEmptyResult.get());
+    Awaitility.await()
+        .pollInterval(10, TimeUnit.MILLISECONDS)
+        .atMost(2, TimeUnit.SECONDS)
+        .until(() -> gotEmptyResult.get());
 
     // Unpause and read the data in th next fetch
     reader.pauseOrResumeSplits(ImmutableList.of(), ImmutableList.of(split));