Java Connection Pooling最佳實踐？

Question

在厭倦了c3p0的常量鎖定之後，我轉向BoneCP來爲我的數據庫提供備用連接池。我有一個服務器應用程序，每分鐘處理大約7000個項目，並且需要將這些項目記錄到我們的MySQL數據庫中。我現在有100個工作線程，並建立了我的游泳池就像這樣：

BoneCPConfig config = new BoneCPConfig(); 
     config.setJdbcUrl("jdbc:mysql://"+Settings.MYSQL_HOSTNAME+"/"+Settings.MYSQL_DATABASE+"?autoReconnectForPools=true"); 
     config.setUsername(Settings.MYSQL_USERNAME); 
     config.setPassword(Settings.MYSQL_PASSWORD); 
     config.setMinConnectionsPerPartition(5); 
     config.setMaxConnectionsPerPartition(10); 
     config.setPartitionCount(5); 
     config.setAcquireIncrement(5); 
     connectionPool = new BoneCP(config); // setup the connection pool 

是這樣的應用程序可以接受的那些設置？我在問，因爲在運行一兩分鐘後，我在嘗試撥打getConnection時遇到了BoneCP異常。謝謝您的幫助。

這是我在工作線程中用於db調用的代碼，它不能在dbConn = this.dbPool.getConnection()行上失敗。我沒有正確關閉連接嗎？

private void insertIntoDb() { 
    try { 
     Connection dbConn = this.dbPool.getConnection(); 

     try { 
      PreparedStatement ps3 = dbConn.prepareStatement("INSERT IGNORE INTO test_table1 SET test1=?, test2=?, test3=?"); 
      ps3.setString(1, "some string"); 
      ps3.setString(2, "some other string"); 
      ps3.setString(3, "more strings"); 
      ps3.execute(); 
      ps3.close(); 

      PreparedStatement ps4 = dbConn.prepareStatement("INSERT IGNORE INTO test_table2 SET test1=?, test2=?, test3=?"); 
      ps4.setString(1, "some string"); 
      ps4.setString(2, "some other string"); 
      ps4.setString(3, "more strings"); 
      ps4.execute(); 
      ps4.close(); 

     } catch(SQLException e) { 
      logger.error(e.getMessage()); 
     } finally { 
      try { 
       dbConn.close(); 
      } catch (SQLException e) { 
       logger.error(e.getMessage()); 
      } 
     } 
    } catch(SQLException e) { 
     logger.error(e.getMessage()); 
    } 
} 

這是我看到的錯誤：

[java] WARN [com.google.common.base.internal.Finalizer] (ConnectionPartition.java:141) - BoneCP detected an unclosed connection and will now attempt to close it for you. You should be closing this connection in your application - enable connectionWatch for additional debugging assistance. 
[java] WARN [com.google.common.base.internal.Finalizer] (ConnectionPartition.java:141) - BoneCP detected an unclosed connection and will now attempt to close it for you. You should be closing this connection in your application - enable connectionWatch for additional debugging assistance. 
[java] WARN [com.google.common.base.internal.Finalizer] (ConnectionPartition.java:141) - BoneCP detected an unclosed connection and will now attempt to close it for you. You should be closing this connection in your application - enable connectionWatch for additional debugging assistance. 
[java] WARN [com.google.common.base.internal.Finalizer] (ConnectionPartition.java:141) - BoneCP detected an unclosed connection and will now attempt to close it for you. You should be closing this connection in your application - enable connectionWatch for additional debugging assistance. 
[java] WARN [com.google.common.base.internal.Finalizer] (ConnectionPartition.java:141) - BoneCP detected an unclosed connection and will now attempt to close it for you. You should be closing this connection in your application - enable connectionWatch for additional debugging assistance. 
[java] WARN [com.google.common.base.internal.Finalizer] (ConnectionPartition.java:141) - BoneCP detected an unclosed connection and will now attempt to close it for you. You should be closing this connection in your application - enable connectionWatch for additional debugging assistance. 
[java] WARN [com.google.common.base.internal.Finalizer] (ConnectionPartition.java:141) - BoneCP detected an unclosed connection and will now attempt to close it for you. You should be closing this connection in your application - enable connectionWatch for additional debugging assistance. 

ERROR pool-2-thread-39 2010-09-04 13:36:19,798 com.test.testpackage.MyTask - null 
java.sql.SQLException 
    at com.jolbox.bonecp.BoneCP.getConnection(BoneCP.java:381) 

Answer 1

是這樣的應用程序可以接受的那些設置？我在問，因爲在運行一兩分鐘後，當我嘗試調用pool上的getConnection時，我收到了boneCP異常。謝謝您的幫助。

如果你有100名工人，爲什麼你限制池的數量爲50個（分區數x每個分區的最大連接數，即5×10）？

我沒有正確關閉連接？

看起來沒問題（但可能啓用connectionWatch暗示，看看警告是關於什麼）。就我個人而言，我關閉了所有使用的資源，包括語句和結果集。以防萬一，這裏是我使用的成語：

Connection conn = null; 
PreparedStatement pstmt = null; 
ResultSet rs = null; 

try { 
    conn = pool.getConnection(); 
    pstmt = conn.prepareStatement(SOME_SQL); 
    pstmt.setFoo(1, foo); 
    ... 
    rs = pstmt.executeQuery(); 
    ... 
} finally { 
    if (rs != null) try { rs.close(); } catch (SQLException quiet) {} 
    if (pstmt != null) try { pstmt.close(); } catch (SQLException quiet) {} 
    if (conn != null) try { conn.close(); } catch (SQLException quiet) {} 
} 

你可以將上述調用分組在一個工具類的靜態方法。

或者你可以使用Commons DbUtils的DbUnit.closeQuietly(Connection, Statement, ResultSet)已經做到這一點。