Lindorm:Develop applications using the Druid connection pool for Java

<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>druid</artifactId>
  <version>1.2.11</version>
</dependency>
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-j</artifactId>
  <version>8.3.0</version>
</dependency>

<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>druid-spring-boot-starter</artifactId>
  <version>1.2.11</version>
  <exclusions>
    <exclusion>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
    </exclusion>
  </exclusions>
</dependency>
<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>druid</artifactId>
  <version>1.2.11</version>
</dependency>
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-j</artifactId>
  <version>8.3.0</version>
</dependency>

# Driver class — keep this unchanged.
driverClassName=com.mysql.cj.jdbc.Driver

# Replace <endpoint> with your LindormTable endpoint for MySQL and <database> with your database name.
# To get the endpoint, see View endpoints: https://www.alibabacloud.com/help/en/lindorm/user-guide/view-endpoints
# Keep the other URL parameters unchanged to maintain optimal performance.
url=jdbc:mysql://<endpoint>:33060/<database>?sslMode=disabled&allowPublicKeyRetrieval=true&useServerPrepStmts=true&useLocalSessionState=true&rewriteBatchedStatements=true&cachePrepStmts=true&prepStmtCacheSize=100&prepStmtCacheSqlLimit=50000000&socketTimeout=120000
username=<username>
password=<password>

# Initialize the connection pool on startup — keep this unchanged.
init=true

# Number of connections to create during initialization.
initialSize=10
# Maximum number of connections in the pool. Set this to match your thread pool size.
maxActive=40
# Minimum number of idle connections. For high-throughput scenarios, set this equal to maxActive.
# For workloads with large fluctuations, use a smaller value.
minIdle=40
# Maximum time (ms) the client waits to get a connection — keep this unchanged.
maxWait=30000

# Limits how many times a single connection can be reused, preventing uneven load
# across Lindorm SQL frontend nodes. Has a minor performance impact.
phyMaxUseCount=30000

# Keep-alive settings — keep these unchanged to prevent unexpected disconnections.
druid.keepAlive=true
# If a connection has been idle for longer than this value (ms), its validity is checked.
druid.keepAliveBetweenTimeMillis=120000
# Interval (ms) at which idle connections are checked for eviction or keep-alive.
timeBetweenEvictionRunsMillis=60000
# Connections idle for longer than this value (ms) are candidates for eviction.
minEvictableIdleTimeMillis=1800000
maxEvictableIdleTimeMillis=1800000

# Connection validation settings — keep these unchanged.
testWhileIdle=true
testOnBorrow=false
testOnReturn=false

Parámetros de conexión

Dimensionamiento del pool de conexiones

Los nodos frontend de Lindorm SQL utilizan Server Load Balancer (SLB) para el balanceo de carga. Evite mantener conexiones abiertas durante periodos prolongados para distribuir las solicitudes uniformemente. Configure phyMaxUseCount para limitar la reutilización de conexiones.

• Establezca maxActive igual al tamaño del pool de hilos de su aplicación.

• Para cargas de trabajo sensibles a la latencia y con alto throughput, establezca minIdle igual a maxActive para que las conexiones estén siempre listas.

• Para cargas de trabajo con fluctuaciones significativas de tráfico, utilice un valor menor en minIdle para reducir el consumo de recursos inactivos.

// Load configuration from druid.properties.
Properties properties = new Properties();
InputStream inputStream = DruidPoolDemo.class.getClassLoader().getResourceAsStream("druid.properties");
properties.load(inputStream);

// Initialize the connection pool.
DataSource dataSource = DruidDataSourceFactory.createDataSource(properties);

String tableName = "sql_table_" + new Random().nextInt(1000);

// Create a table.
try (Connection connection = dataSource.getConnection()) {
    try (Statement statement = connection.createStatement()) {
        String sql = "create table if not exists " + tableName + "(id VARCHAR, name VARCHAR, primary key(id))";
        int ret = statement.executeUpdate(sql);
        System.out.println(ret);
    }
}

// Insert a single row.
try (Connection connection = dataSource.getConnection()) {
    String sql = "insert into " + tableName + "(id,name) values(?,?)";
    try (PreparedStatement ps = connection.prepareStatement(sql)) {
        ps.setString(1, "aa");
        ps.setString(2, "bb");
        int ret = ps.executeUpdate();
        System.out.println(ret);
    }
}

// Batch insert.
String insertSql = "insert into " + tableName + "(id,name) values(?,?)";
int batchSize = 100;
try (Connection connection = dataSource.getConnection()) {
    try (PreparedStatement ps = connection.prepareStatement(insertSql)) {
        for (int i = 0; i < batchSize; i++) {
            ps.setString(1, "aa" + i);
            ps.setString(2, "bb" + i);
            ps.addBatch();
        }
        ps.executeBatch();
    }
}

// Query data.
try (Connection connection = dataSource.getConnection()) {
    String sql = "select * from " + tableName + " where id=?";
    try (PreparedStatement ps = connection.prepareStatement(sql)) {
        ps.setString(1, "aa");
        ResultSet rs = ps.executeQuery();
        while (rs.next()) {
            String id = rs.getString(1);
            String name = rs.getString(2);
            System.out.println("id=" + id);
            System.out.println("name=" + name);
        }
    }
}

// Delete data.
try (Connection connection = dataSource.getConnection()) {
    String sql = "delete from " + tableName + " where id=?";
    try (PreparedStatement ps = connection.prepareStatement(sql)) {
        ps.setString(1, "aa");
        ps.executeUpdate();
    }
}

Manejo de interrupciones de conexión

En entornos de red complejos, pueden producirse interrupciones de conexión debido a cuellos de botella en la puerta de enlace, inestabilidad de la red o alta pérdida de paquetes. La configuración de keep-alive en druid.properties ayuda a mantener las conexiones inactivas, pero también debe implementar un mecanismo de reintento en el código de su aplicación para fallos transitorios.

Cuando el servidor se actualiza y reinicia, las conexiones activas pueden interrumpirse temporalmente. Capture las excepciones y reintente la operación.

Supervisión del pool de conexiones

Verifique periódicamente las configuraciones efectivas y las estadísticas del pool de conexiones, y revise las configuraciones en los registros:

druidDataSource.getStatData();  // Returns current pool statistics
druidDataSource.dump();         // Logs detailed pool configuration and state

jdbc:mysql://<endpoint>:33060/<database>?sslMode=disabled&allowPublicKeyRetrieval=true&useServerPrepStmts=true&useLocalSessionState=true&rewriteBatchedStatements=true&cachePrepStmts=true&prepStmtCacheSize=100&prepStmtCacheSqlLimit=50000000&socketTimeout=120000