Remove the ConnectionPool warning size feature

ebean-datasource-api/src/main/java/io/ebean/datasource/DataSourceAlert.java

@@ -23,8 +23,4 @@ public interface DataSourceAlert {
    */
   void dataSourceDown(DataSource dataSource, SQLException reason);
 
-  /**
-   * Send an alert to say the dataSource is getting close to its max size.
-   */
-  void dataSourceWarning(DataSource dataSource, String msg);
 }

ebean-datasource-api/src/main/java/io/ebean/datasource/DataSourcePool.java

@@ -133,23 +133,4 @@ default SQLException getDataSourceDownReason() {
    */
   void setMaxSize(int max);
 
-  /**
-   * Deprecated - looking to remove.
-   * <p>
-   * Set a new maximum size. The pool should respect this new warning level immediately
-   * and not require a restart. We may want to increase the maxConnections if the
-   * pool gets large and hits the warning levels.
-   */
-  @Deprecated(forRemoval = true)
-  void setWarningSize(int warningSize);
-
-  /**
-   * Deprecated - looking to remove.
-   * <p>
-   * Return the warning size. When the pool hits this size it can send a
-   * warning message to an administrator.
-   */
-  @Deprecated(forRemoval = true)
-  int getWarningSize();
-
 }

ebean-datasource/src/main/java/io/ebean/datasource/pool/ConnectionPool.java

@@ -70,10 +70,8 @@ final class ConnectionPool implements DataSourcePool {
    */
   private final AtomicBoolean dataSourceUp = new AtomicBoolean(false);
   private SQLException dataSourceDownReason;
-  private final AtomicBoolean inWarningMode = new AtomicBoolean();
   private final int minConnections;
   private int maxConnections;
-  private int warningSize;
   private final int waitTimeoutMillis;
   private final int pstmtCacheSize;
   private final PooledConnectionQueue queue;
@@ -276,19 +274,6 @@ public SQLException dataSourceDownReason() {
     return dataSourceDownReason;
   }
 
-  /**
-   * Called when the pool hits the warning level.
-   */
-  void notifyWarning(String msg) {
-    if (inWarningMode.compareAndSet(false, true)) {
-      // send an Error to the event log...
-      Log.warn(msg);
-      if (notify != null) {
-        notify.dataSourceWarning(this, msg);
-      }
-    }
-  }
-
   private void notifyDataSourceIsDown(SQLException reason) {
     if (dataSourceUp.get()) {
       reset();
@@ -448,17 +433,6 @@ int minSize() {
     return minConnections;
   }
 
-  @Override
-  public void setWarningSize(int warningSize) {
-    queue.setWarningSize(warningSize);
-    this.warningSize = warningSize;
-  }
-
-  @Override
-  public int getWarningSize() {
-    return warningSize;
-  }
-
   /**
    * Return the time in millis that threads will wait when the pool has hit
    * the max size. These threads wait for connections to be returned by the
@@ -587,7 +561,6 @@ PooledConnection createConnectionForQueue(int connId) throws SQLException {
    */
   private void reset() {
     queue.reset(leakTimeMinutes);
-    inWarningMode.set(false);
   }
 
   /**

ebean-datasource/src/main/java/io/ebean/datasource/pool/PooledConnectionQueue.java

@@ -35,10 +35,8 @@ final class PooledConnectionQueue {
   private final Condition notEmpty;
   private int connectionId;
   private final long waitTimeoutMillis;
-  private final long leakTimeMinutes;
   private final long maxAgeMillis;
   private final int minSize;
-  private int warningSize;
   private int maxSize;
   /**
    * Number of threads in the wait queue.
@@ -72,9 +70,7 @@ final class PooledConnectionQueue {
     this.name = pool.name();
     this.minSize = pool.minSize();
     this.maxSize = pool.maxSize();
-    this.warningSize = pool.getWarningSize();
     this.waitTimeoutMillis = pool.waitTimeoutMillis();
-    this.leakTimeMinutes = pool.leakTimeMinutes();
     this.maxAgeMillis = pool.maxAgeMillis();
     this.validateStaleMillis = pool.validateStaleMillis();
     this.busyList = new BusyConnectionBuffer(maxSize, 20);
@@ -128,18 +124,6 @@ void setMaxSize(int maxSize) {
     }
   }
 
-  void setWarningSize(int warningSize) {
-    lock.lock();
-    try {
-      if (warningSize > this.maxSize) {
-        throw new IllegalArgumentException("warningSize " + warningSize + " > maxSize " + this.maxSize);
-      }
-      this.warningSize = warningSize;
-    } finally {
-      lock.unlock();
-    }
-  }
-
   private int totalConnections() {
     return freeList.size() + busyList.size();
   }
@@ -253,7 +237,6 @@ private PooledConnection _obtainConnection() throws InterruptedException, SQLExc
           if (Log.isLoggable(DEBUG)) {
             Log.debug("DataSource [{0}] grow; id[{1}] busy[{2}] max[{3}]", name, c.name(), busySize, maxSize);
           }
-          checkForWarningSize();
           return c;
         }
       }
@@ -422,23 +405,6 @@ void closeBusyConnections(long leakTimeMinutes) {
     }
   }
 
-  /**
-   * As the pool grows it gets closer to the maxConnections limit. We can send
-   * an Alert (or warning) as we get close to this limit and hence an
-   * Administrator could increase the pool size if desired.
-   * <p>
-   * This is called whenever the pool grows in size (towards the max limit).
-   */
-  private void checkForWarningSize() {
-    // the total number of connections that we can add
-    // to the pool before it hits the maximum
-    int availableGrowth = (maxSize - totalConnections());
-    if (availableGrowth < warningSize) {
-      closeBusyConnections(leakTimeMinutes);
-      pool.notifyWarning("DataSource [" + name + "] is [" + availableGrowth + "] connections from its maximum size.");
-    }
-  }
-
   String getBusyConnectionInformation() {
     return getBusyConnectionInformation(false);
   }

ebean-datasource/src/test/java/io/ebean/datasource/pool/ConnectionPoolDbOutageTest.java

@@ -25,17 +25,15 @@ public class ConnectionPoolDbOutageTest implements DataSourceAlert, WaitFor {
   private static final Logger log = LoggerFactory.getLogger(ConnectionPoolDbOutageTest.class);
   private String connString;
   private Connection h2Conn;
-  
+
   private int up;
   private int down;
-  private int warn;
-
-
+
   @AfterEach
   void afterAll() throws SQLException {
     h2Conn.close();
   }
-  
+
   /**
    * Changes the password and closes all exisitng sessions.
    */
@@ -47,11 +45,11 @@ void setPassword(String pw) throws SQLException {
         sessions.add(rs.getInt(1));
       }
     }
-    
+
     try (Statement stmt = h2Conn.createStatement()) {
       stmt.execute("alter user sa set password '" + pw + "'");
     }
-    
+
     h2Conn.close();
     // reopen connection with new credentials and kill old session
     h2Conn = DriverManager.getConnection(connString, "sa", pw);
@@ -82,11 +80,11 @@ private DataSourceConfig config() {
   public void testOfflineFromStart() throws InterruptedException, SQLException {
     connString = "jdbc:h2:mem:testOfflineFromStart";
     h2Conn = DriverManager.getConnection(connString, "sa", "unknown");
-    
+
     DataSourceConfig config = config();
     assertThat(down).isEqualTo(0);
     ConnectionPool pool = new ConnectionPool("mem:testOfflineFromStart", config);
-    // 
+
     waitFor(() -> {
       assertThat(pool.isOnline()).isFalse();
       assertThat(up).isEqualTo(0);
@@ -104,14 +102,13 @@ public void testOfflineFromStart() throws InterruptedException, SQLException {
       assertThat(down).isEqualTo(1);
       assertThat(pool.size()).isEqualTo(1);
     });
-
   }
 
   @Test
   public void testOfflineDuringRun() throws InterruptedException, SQLException {
     connString = "jdbc:h2:mem:testOfflineDuringRun";
     h2Conn = DriverManager.getConnection(connString, "sa", "sa");
-  
+
     DataSourceConfig config = config();
     ConnectionPool pool = new ConnectionPool("testOfflineDuringRun", config);
     waitFor(()-> {
@@ -121,15 +118,15 @@ public void testOfflineDuringRun() throws InterruptedException, SQLException {
       assertThat(pool.size()).isEqualTo(3);
     });
     log.info("pool created ");
-    
+
     // simulate an outage
     setPassword("outage");
     waitFor(()-> {
       assertThat(pool.isOnline()).isFalse();
       assertThat(up).isEqualTo(1);
       assertThat(down).isEqualTo(1);
     });
-  
+
     // recover from outage
     setPassword("sa");
     waitFor(()-> {
@@ -148,9 +145,4 @@ public void dataSourceUp(DataSource dataSource) {
   public void dataSourceDown(DataSource dataSource, SQLException reason) {
     down++;
   }
-
-  @Override
-  public void dataSourceWarning(DataSource dataSource, String msg) {
-    warn++;
-  }
 }