tomcat7 jdk7 ubuntu tomcat经常报下面的异常，什么原因？

Question

log4j:WARN No appenders could be found for logger (org.springframework.web.context.support.XmlWebApplicationContext).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc
SEVERE: The web application [] registered the JDBC driver [com.mysql.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcib
ly unregistered.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [FileWatchdog] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [Timer-0] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [MySQL Statement Cancellation Timer] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads

SEVERE: The web application [] appears to have started a thread named [Timer-0] but has failed to stop it. This is very likely to create a memory leak.

Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [MySQL Statement Cancellation Timer] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application [] appears to have started a thread named [Timer-1] but has failed to stop it. This is very likely to create a memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Sep 28, 2015 4:10:04 PM org.apache.coyote.AbstractProtocol stop
INFO: Stopping ProtocolHandler ["http-bio-8080"]
Sep 28, 2015 4:10:04 PM org.apache.coyote.AbstractProtocol stop
INFO: Stopping ProtocolHandler ["ajp-bio-8009"]
Sep 28, 2015 4:10:04 PM org.apache.coyote.AbstractProtocol destroy
INFO: Destroying ProtocolHandler ["http-bio-8080"]
Sep 28, 2015 4:10:04 PM org.apache.coyote.AbstractProtocol destroy

Answer 1

这样做的理由是什么？异常是什么引起的？

Answer 2

解决了没？ 好像是linux并发数量还是怎么的，对linux不是很了解；

Answer 3

but has failed to stop it. This is very likely to create a memory leak.跟我碰到的情况很像，

http://my.oschina.net/stonezing/blog/497920 

Answer 4

The web application [] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@cb54fdf]) 这是啥玩意儿，内存撑爆了