[alibaba/druid]2.x版本出现：发送到后端时发生I/O错误

1、请提供详细的异常堆栈。 2、也请检查两种情况下，是否pg驱动版本不一致。

1、请提供详细的异常堆栈。 2、也请检查两种情况下，是否pg驱动版本不一致。

1、附件提供日志片段 2、pgJDBC驱动版本一致 druid.txt

我也存在相同的问题，最后也是将druid的版本改到1.1.24该问题不再重现。 1、期间尝试过对test-on-borrow和test-on-return改为true，未能解决； 2、pg的jdbc驱动版本42.3.8，版本一致。也改过驱动版本到最新，排除了pg的驱动问题； 3、目前验证sql主要是select count(1) from table，在table数据量大于30万之后能复现此报错； 4、遇到的错误druid版本是1.2.14，也尝试过1.2.16，问题相同； 5、报错日志（druid版本1.2.14，pg_jdbc42.3.8）片段如下：### Error querying database. Cause: org.postgresql.util.PSQLException: An I/O error occurred while sending to the backend.java.net.SocketTimeoutException: Read timed out at java.net.SocketInputStream.socketRead0(Native Method) ~[na:1.8.0_351] at java.net.SocketInputStream.socketRead(SocketInputStream.java:116) ~[na:1.8.0_351] at java.net.SocketInputStream.read(SocketInputStream.java:171) ~[na:1.8.0_351] at java.net.SocketInputStream.read(SocketInputStream.java:141) ~[na:1.8.0_351] at org.postgresql.core.VisibleBufferedInputStream.readMore(VisibleBufferedInputStream.java:161) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.core.VisibleBufferedInputStream.ensureBytes(VisibleBufferedInputStream.java:128) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.core.VisibleBufferedInputStream.ensureBytes(VisibleBufferedInputStream.java:113) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.core.VisibleBufferedInputStream.read(VisibleBufferedInputStream.java:73) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.core.PGStream.receiveChar(PGStream.java:453) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2119) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:355) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:490) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:408) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.jdbc.PgPreparedStatement.executeWithFlags(PgPreparedStatement.java:167) ~[postgresql-42.3.8.jar:42.3.8] at org.postgresql.jdbc.PgPreparedStatement.execute(PgPreparedStatement.java:156) ~[postgresql-42.3.8.jar:42.3.8] at com.alibaba.druid.pool.DruidPooledPreparedStatement.execute(DruidPooledPreparedStatement.java:483) ~[druid-1.2.14.jar:na] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_351] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_351] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_351] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_351] at org.apache.ibatis.logging.jdbc.PreparedStatementLogger.invoke(PreparedStatementLogger.java:59) ~[mybatis-3.4.6.jar:3.4.6] at com.sun.proxy.$Proxy241.execute(Unknown Source) ~[na:na] at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:63) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:326) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) ~[mybatis-3.4.6.jar:3.4.6] at com.github.pagehelper.util.ExecutorUtil.executeAutoCount(ExecutorUtil.java:138) ~[pagehelper-5.1.7.jar:na] at com.github.pagehelper.PageInterceptor.count(PageInterceptor.java:148) ~[pagehelper-5.1.7.jar:na] at com.github.pagehelper.PageInterceptor.intercept(PageInterceptor.java:97) ~[pagehelper-5.1.7.jar:na] at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61) ~[mybatis-3.4.6.jar:3.4.6] at com.sun.proxy.$Proxy239.query(Unknown Source) ~[na:na] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) ~[mybatis-3.4.6.jar:3.4.6] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_351] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_351] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_351] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_351] at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433) ~[mybatis-spring-1.3.2.jar:1.3.2] at com.sun.proxy.$Proxy85.selectList(Unknown Source) ~[na:na] at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:230) ~[mybatis-spring-1.3.2.jar:1.3.2] at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:139) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:76) ~[mybatis-3.4.6.jar:3.4.6] at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59) ~[mybatis-3.4.6.jar:3.4.6] at com.sun.proxy.$Proxy175.getLteDay(Unknown Source) ~[na:na]

1、请提供详细的异常堆栈。 2、也请检查两种情况下，是否pg驱动版本不一致。 目前我们的环境也出现了问题，在普通的数据库操作没有问题。时间长一点的数据库访问，就会出现 【org.postgresql.util.PSQLException: An I/O error occurred while sending to the backend.】 【Caused by: java.net.SocketTimeoutException: Read timed out】 程序没有改动只是升级了druid-1.2.16.jar或者1.2.17.jar 请尽快看一下，很多人都出现了这个问题。 postgresql-42.6.0.jar

我也出现这种问题。升级到1.2.18就出现这种问题。 SQL请求稍微耗时长一点的就返回不出来。: An I/O error occurred while sending to the backend

有人解决了吗

@enchanterzj @changuoqiang @guochunjiang @xxd-China 你们应该将 Druid 升级到 1.2.15 或更高版本，这个版本修复了这个问题（https://github.com/alibaba/druid/issues/5096）。