Имеется ошибка вот такого рода:

com.mysql.jdbc.CommunicationsException: The driver was unable to create a connection due to an inability to establish the client portion of a socket.

This is usually caused by a limit on the number of sockets imposed by the operating system. This limit is usually configurable.

For Unix-based platforms, see the manual page for the 'ulimit' command. Kernel or system reconfiguration may also be required.

For Windows-based platforms, see Microsoft Knowledge Base Article 196271 (Q196271).


Ошибка возникает при обрабатывании запроса SELECT * FROM tableName.

Это он родимый и есть =)


SQL Exception while getting DB connection: com.mysql.jdbc.CommunicationsException: The driver was unable to create a connection due to an inability to establish the client portion of a socket.

This is usually caused by a limit on the number of sockets imposed by the operating system. This limit is usually configurable.

For Unix-based platforms, see the manual page for the 'ulimit' command. Kernel or system reconfiguration may also be required.

For Windows-based platforms, see Microsoft Knowledge Base Article 196271 (Q196271).
авг 10, 2012 4:25:48 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [by.belgaz.servlet.PersonalAccountSearchServlet] in context with path [/requestsForAlarm] threw exception
java.lang.NullPointerException
at by.belgaz.impl.GRSImplDB.getGRP(GRSImplDB.java:201)
at by.belgaz.impl.AddressImplDB.getPersonalAddress(AddressImplDB.java:92)
at by.belgaz.impl.SubscribeImplDB.getPersonsByName(SubscribeImplDB.java:486)
at by.belgaz.servlet.PersonalAccountSearchServlet.doGet(PersonalAccountSearchServlet.java:177)
at by.belgaz.servlet.PersonalAccountSearchServlet.doPost(PersonalAccountSearchServlet.java:200)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1001)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

Все что синим цветом выделено - это события, наступающие из-за того что вывелось раньше =)

Красный цвет - это мой обработчик ошибок.

Вот то, что выдал мне трассировщик e.printStackTrace();

com.mysql.jdbc.CommunicationsException: The driver was unable to create a connection due to an inability to establish the client portion of a socket.

This is usually caused by a limit on the number of sockets imposed by the operating system. This limit is usually configurable.

For Unix-based platforms, see the manual page for the 'ulimit' command. Kernel or system reconfiguration may also be required.

For Windows-based platforms, see Microsoft Knowledge Base Article 196271 (Q196271).
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2847)
at com.mysql.jdbc.Connection.<init>(Connection.java:1555)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at by.belgaz.iface.BaseDBIface.getConnection(BaseDBIface.java:31)
at by.belgaz.impl.AddressImplDB.getPersonalAddress(AddressImplDB.java:40)
at by.belgaz.impl.SubscribeImplDB.getPersonsByName(SubscribeImplDB.java:486)
at by.belgaz.servlet.PersonalAccountSearchServlet.doGet(PersonalAccountSearchServlet.java:177)
at by.belgaz.servlet.PersonalAccountSearchServlet.doPost(PersonalAccountSearchServlet.java:200)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1001)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

Странно, но сегодня такой ошибки нету.
Проблемы возникали на SELECT, который выбирал все записи из огромной таблицы. Адски грузился ЦП, а потом опа и все ЦА загружен на 5%, коннекта к БД нету. Открытый коннекшен не закрыт, но нулевой. Т.е. проблема возникла после перезагрузки и решилась очередной перезагрузкой. Видимых неисправностей я не вижу.