xue2lang opened a new issue #13539: URL: https://github.com/apache/shardingsphere/issues/13539
## Bug Report **For English only**, other languages will not accept. Before report a bug, make sure you have: - Searched open and closed [GitHub issues](https://github.com/apache/shardingsphere/issues). - Read documentation: [ShardingSphere Doc](https://shardingsphere.apache.org/document/current/en/overview). Please pay attention on issues you submitted, because we maybe need more details. If no response anymore and we cannot reproduce it on current information, we will **close it**. Please answer these questions before submitting your issue. Thanks! ### Which version of ShardingSphere did you use? 5.0.0-beta ### Which project did you use? ShardingSphere-JDBC or ShardingSphere-Proxy? ShardingSphere-JDBC ### Expected behavior execute sql right ### Actual behavior ```java java.sql.SQLTransientConnectionException: xx Connection is not available, request timed out after 2000ms. ``` ### Reason analyze (If you can) ```java Class ShardingSphereConnection code ： @Override public List<Connection> getConnections(final String dataSourceName, final int connectionSize, final ConnectionMode connectionMode) throws SQLException { DataSource dataSource = dataSourceMap.get(dataSourceName); Preconditions.checkState(null != dataSource, "Missing the data source name: '%s'", dataSourceName); Collection<Connection> connections; // **step：1** synchronized (getCachedConnections()) { connections = getCachedConnections().get(dataSourceName); } List<Connection> result; if (connections.size() >= connectionSize) { result = new ArrayList<>(connections).subList(0, connectionSize); } else if (!connections.isEmpty()) { result = new ArrayList<>(connectionSize); result.addAll(connections); List<Connection> newConnections = createConnections(dataSourceName, dataSource, connectionSize - connections.size(), connectionMode); result.addAll(newConnections); synchronized (getCachedConnections()) { getCachedConnections().putAll(dataSourceName, newConnections); } } else { // **step：2** result = new ArrayList<>(createConnections(dataSourceName, dataSource, connectionSize, connectionMode)); synchronized (getCachedConnections()) { getCachedConnections().putAll(dataSourceName, result); } } return result; } ``` ### Steps to reproduce the behavior, such as: SQL to execute, sharding rule configuration, when exception occur etc. ```java connection pool size min=max=2 we have thread a、b、c - thread a get the cpu control，in step 1， CachedConnection is empty，release cpu control - thread b get the cpu control，in step 1， CachedConnection is empty，use execute step2 and cache connection，release cpu control - thread c get the cpu control，in step 1， CachedConnection is empty，use execute step2 and cache connection，release cpu control - thread a get cpu control ,use execute step2 ,but no datasource can get from datasource connection pool ``` ### Example codes for reproduce this issue (such as a github link). ```java public void sharding删除查询() throws SQLException, InterruptedException { Connection connection = getShardingConnection(); TimeUnit unit = TimeUnit.SECONDS; BlockingQueue workQueue = new LinkedBlockingQueue<>(10); ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(16, 16, 10, unit, workQueue); threadPoolExecutor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy()); //删除 int num = 500; CountDownLatch count = new CountDownLatch(num); while (num > 0) { threadPoolExecutor.execute(()->{ List<Object> params = new ArrayList<>(); params.add(nextLong()); params.add(nextLong()); try ( PreparedStatement preparedStatement = connection.prepareStatement(deleteSQL);) { for (int i = 0; i < params.size(); i++) { preparedStatement.setObject(i + 1, params.get(i)); } preparedStatement.executeUpdate(); } catch (Exception e) { System.out.println(e); }finally { count.countDown(); } }); num--; } count.await(); connection.close(); } ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
