mysql  出现大量sleep进程处理    

一般是默认连接时间的设置,可以先查询一下 参数

show global variables like 'wait_timeout';  默认值是28800  差不多是8个小时有效时间 

网上推荐设置是10

set global wait_timeout=10;

以上为全局变量

show variables like 'wait_timeout';

set  wait_timeout=10;

以上为session 环境变理

虽然能解决sleep进程问题  但是也有后遗症, 会出现以下错误

Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 4,301,488 milliseconds ago.  The last packet sent successfully to the server was 0 milliseconds ago.

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_111]

at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_111]

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[na:1.8.0_111]

at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[na:1.8.0_111]

at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3030) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2916) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3459) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1957) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2107) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2648) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2086) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2237) ~[mysql-connector-5.1.8.jar:na]

at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76) ~[c3p0-0.9.1.2.jar:0.9.1.2]

at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:82) ~[hibernate-core-4.3.11.Final.jar:4.3.11.Final]

... 103 common frames omitted

Caused by: java.net.SocketException: Software caused connection abort: recv failed

at java.net.SocketInputStream.socketRead0(Native Method) ~[na:1.8.0_111]

at java.net.SocketInputStream.socketRead(Unknown Source) ~[na:1.8.0_111]

at java.net.SocketInputStream.read(Unknown Source) ~[na:1.8.0_111]

at java.net.SocketInputStream.read(Unknown Source) ~[na:1.8.0_111]

at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:113) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:160) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:188) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2472) ~[mysql-connector-5.1.8.jar:na]

at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2927) ~[mysql-connector-5.1.8.jar:na]

... 112 common frames omitted

这表示wait_timeout 时间太小 导致的 需要调大一点就能解决.

如果还报此错误  还可以设置此参数

执行set global interactive_timeout=1814400;