diff --git a/services/core/java/com/android/server/notification/NotificationHistoryDatabase.java b/services/core/java/com/android/server/notification/NotificationHistoryDatabase.java
index 377e731fbeeb4..2e8b76ee75fad 100644
--- a/services/core/java/com/android/server/notification/NotificationHistoryDatabase.java
+++ b/services/core/java/com/android/server/notification/NotificationHistoryDatabase.java
@@ -266,13 +266,17 @@ public class NotificationHistoryDatabase {
                     mHistoryFiles.removeLast();
                 } else {
                     // all remaining files are newer than the cut off; schedule jobs to delete
-                    final long deletionTime = creationTime + (retentionDays * HISTORY_RETENTION_MS);
-                    scheduleDeletion(currentOldestFile.getBaseFile(), deletionTime);
+                    scheduleDeletion(currentOldestFile.getBaseFile(), creationTime, retentionDays);
                 }
             }
         }
     }
 
+    private void scheduleDeletion(File file, long creationTime, int retentionDays) {
+        final long deletionTime = creationTime + (retentionDays * HISTORY_RETENTION_MS);
+        scheduleDeletion(file, deletionTime);
+    }
+
     private void scheduleDeletion(File file, long deletionTime) {
         if (DEBUG) {
             Slog.d(TAG, "Scheduling deletion for " + file.getName() + " at " + deletionTime);
@@ -330,17 +334,28 @@ public class NotificationHistoryDatabase {
         }
     };
 
-    private final class WriteBufferRunnable implements Runnable {
+    final class WriteBufferRunnable implements Runnable {
+        long currentTime = 0;
+        AtomicFile latestNotificationsFile;
+
         @Override
         public void run() {
             if (DEBUG) Slog.d(TAG, "WriteBufferRunnable");
             synchronized (mLock) {
-                final AtomicFile latestNotificationsFiles = new AtomicFile(
-                        new File(mHistoryDir, String.valueOf(System.currentTimeMillis())));
+                if (currentTime == 0) {
+                    currentTime = System.currentTimeMillis();
+                }
+                if (latestNotificationsFile == null) {
+                    latestNotificationsFile = new AtomicFile(
+                            new File(mHistoryDir, String.valueOf(currentTime)));
+                }
                 try {
-                    writeLocked(latestNotificationsFiles, mBuffer);
-                    mHistoryFiles.addFirst(latestNotificationsFiles);
+                    writeLocked(latestNotificationsFile, mBuffer);
+                    mHistoryFiles.addFirst(latestNotificationsFile);
                     mBuffer = new NotificationHistory();
+
+                    scheduleDeletion(latestNotificationsFile.getBaseFile(), currentTime,
+                            HISTORY_RETENTION_DAYS);
                 } catch (IOException e) {
                     Slog.e(TAG, "Failed to write buffer to disk. not flushing buffer", e);
                 }
@@ -440,7 +455,7 @@ public class NotificationHistoryDatabase {
 
         @Override
         public void run() {
-            if (DEBUG) Slog.d(TAG, "RemoveConversationRunnable");
+            if (DEBUG) Slog.d(TAG, "RemoveConversationRunnable " + mPkg + " "  + mConversationId);
             synchronized (mLock) {
                 // Remove from pending history
                 mBuffer.removeConversationFromWrite(mPkg, mConversationId);
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/NotificationHistoryDatabaseTest.java b/services/tests/uiservicestests/src/com/android/server/notification/NotificationHistoryDatabaseTest.java
index b7bcbfb055312..7e5469090d82e 100644
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationHistoryDatabaseTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationHistoryDatabaseTest.java
@@ -328,4 +328,26 @@ public class NotificationHistoryDatabaseTest extends UiServiceTestCase {
         verify(nh).removeConversationFromWrite("pkg", "convo");
         verify(af, never()).startWrite();
     }
+
+    @Test
+    public void testWriteBufferRunnable() throws Exception {
+        NotificationHistory nh = mock(NotificationHistory.class);
+        when(nh.getPooledStringsToWrite()).thenReturn(new String[]{});
+        when(nh.getNotificationsToWrite()).thenReturn(new ArrayList<>());
+        NotificationHistoryDatabase.WriteBufferRunnable wbr =
+                mDataBase.new WriteBufferRunnable();
+
+        mDataBase.mBuffer = nh;
+        wbr.currentTime = 5;
+        wbr.latestNotificationsFile = mock(AtomicFile.class);
+        File file = mock(File.class);
+        when(file.getName()).thenReturn("5");
+        when(wbr.latestNotificationsFile.getBaseFile()).thenReturn(file);
+
+        wbr.run();
+
+        assertThat(mDataBase.mHistoryFiles.size()).isEqualTo(1);
+        assertThat(mDataBase.mBuffer).isNotEqualTo(nh);
+        verify(mAlarmManager, times(1)).setExactAndAllowWhileIdle(anyInt(), anyLong(), any());
+    }
 }