Help Needed for Root cause - Apache & Tomcat Services got stopped.

[Sahil Verma]

Hi Team,

We are using both Apache & Tomcat environment. Kindly advise for the below error logs of Apache and Tomcat -

Apache - 2.4.25 version
Tomcat - 8.5.5 version
OS - Linux

Both Apache and Tomcat services got stopped. We have gone through the logs and found errors related to MaxRequestWorkers in httpd Apache logs.

[Thu May 05 10:34:51.441668 2022] [mpm_event:error] [pid 27440:tid
140464737793792] AH00484: server reached MaxRequestWorkers setting,
consider raising the MaxRequestWorkers setting


And in Tomcat logs, found memory leakage warnings -

05-May-2022 11:28:48.058 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesJdbc The web application [thq] registered the JDBC driver [com.ibm.db2.jcc.DB2Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
05-May-2022 11:28:48.058 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesJdbc The web application [thq] registered the JDBC driver [com.teradata.jdbc.TeraDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
05-May-2022 11:28:48.063 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [thq] appears to have started a thread named [Timer-0] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
05-May-2022 11:28:48.064 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [thq] appears to have started a thread named [Thread-12] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
05-May-2022 11:28:48.065 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [thq] appears to have started a thread named [JMSCCThreadPoolMaster] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
05-May-2022 11:28:48.066 SEVERE [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.checkThreadLocalMapForLeaks The web application [thq] created a ThreadLocal with key of type [com.ibm.msg.client.jms.internal.JmsTls$1] (value [com.ibm.msg.client.jms.internal.JmsTls$1@17a957aa]) and a value of type [com.ibm.msg.client.jms.internal.JmsTls] (value [com.ibm.msg.client.jms.internal.JmsTls@10456393]) 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.


Regards,
Sahil