Server Stop responding because of [Pool-Cleaner]:Tomcat Connection Pool but has failed to stop it. This is very likely to create a memory leak

Question

Problem:

org.apache.catalina.loader.WebappClassLoader - The web application [/…] appears to have started a thread named [[Pool-Cleaner]:Tomcat Connection Pool[...] but has failed to stop it. This is very likely to create a memory leak.

I have few application deployed in a tomcat server(tomcat-7.0.23) with jdk1.6.0_45 and the server i register with apache webserver. After staring the server it is working fine until i get the above error for all the application separately all of a sudden and after that my tomcat giving 404 for all request but the tomcat process is still up and in browser it shows "FILE NOT FOUND".

we use Tomcat connection pool with following configuration:

<Resource 
name="Project1" 
auth="Container" 
type="javax.sql.DataSource" 
factory="org.apache.tomcat.jdbc.pool.DataSourceFactory" 
url="DatabaseName" 
username="_username" 
password="_Password" 
driverClassName="com.microsoft.sqlserver.jdbc.SQLServerDriver" 
initialSize="40"
maxActive="300" 
maxIdle="250" 
minIdle="90"
maxWait="10000" 
minEvictableIdleTimeMillis="300000" 
timeBetweenEvictionRunsMillis="120000"
validationInterval="30000"
validationQuery="SELECT 1" 
testOnBorrow="true" 
logAbandoned="true"
removeAbandoned="true" 
removeAbandonedTimeout="60" 
abandonWhenPercentageFull="50"
jdbcInterceptors="ResetAbandonedTimer"
/>

And the configuration is in context.xml file.

Answer 1

That memory leak warning is correct. It refers to a known issue in Tomcat 7.0.x that was fixed a few weeks ago ( r1744702 ) and will be included in 7.0.70 onwards.