-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Louis,
On 9/26/18 14:42, Louis Zipes wrote: > Hi all, Tomcat 7.0.54 running on Windows 2012 > > We are running a third party application on Tomcat and today we > have intermittently run in issues where the application stops > working. The big changes in our system is that we have added more > end users and we are at year end so of course everyone is hitting > the system hard. Even if we force a log out of all users and stop > all background jobs then the application doesn't recover. > > We see no active sessions on the database (our application is > connecting to an Oracle database) and I see no clear error messages > in either our third party application logs or the Tomcat logs (ex. > OutofMemory). When we go to the Windows Task Manager we did not > see the machine's Memory max'd out but admittedly I didn't look at > the Java session to see if was reaching its Heap Max. The only > thing that we noticed was that TCP connections went down right > after the restart. I did open up Jconsole under Java and I did > force a garbage collection but that didn't seem to help. > > We do have an Oracle Grid Control and we did get an alert in > regards to Metric: [HTTP Transaction] Perceived Time per Page going > past thresholds but not sure if that was just an old alert with and > old range that was set up a long time ago or is a really valid > clue. Since this is PRD we had to get it back up and running so > all I did was increase the Tomcat Xmx Heap size and restarted. I'm > not really confident that is the solution since as mentioned you > tend to see a clear out of memory error if it was too small. > > So a few questions: > > > 1) Does this sound like a known issue with this earlier version > of Tomcat? No. > 2) Should I turn up any logging on Tomcat and if so which > ones? Not yet. > 3) We didn't do a JSTACK dump while it was happening. Would > that have been useful? Absolutely. > 4) Do we need to play around with MaxThreads and/or > MaxConnections. We do have maxThreads in our server.mxl but in DEV > when we turned it down to a value = 5 hoping to overwhelm it > nothing bad happened. Don't change anything, yet. > Once again, we are limited to what we could do and collect since it > was PRD and we needed to restart it. We restarted the Tomcat > service and everything is processing fine for right now. I will > note that that we did have that bad Windows patch that prevented it > from stopping and starting cleanly > (https://stackoverflow.com/questions/51498291/tomcat-lockup-on-shutdow n) > but we have taken the break fix patch and the daily restarts seem > to be fine since then. > > Any comments/suggestions are appreciated! Your most likely problem is database connection pool mismanagement: connections aren't properly released and the pool empties. All threads are left waiting on available database connections which will never be replenished. - -chris -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Thunderbird - https://www.enigmail.net/ iQIzBAEBCAAdFiEEMmKgYcQvxMe7tcJcHPApP6U8pFgFAlur4fgACgkQHPApP6U8 pFhq/RAAwZixHqbHxYdX3VCrTfvz0tnOmu7W4sbeFqhExV+M6NVL2LK1RO26eTq5 OJB2o/RheCeajWHxqiJQY4ERMTOyyqZYCsRG9L901heW2UAW122zeX7hhXDB1IMo qIBVYQalg1j5e2Lw9MqT3ISj6U/GNA6VlirTAHGtuEBBpKXXyb6KtmOgpjHjjXS7 mTYni2iTHO/NaGrS519alFPMBnF4Wq5NzRcLewNMqj9Nbx2uu3Suu95DhJ+WIIep DOmyy4UGHxGx2QqNUnVWMHApGGjFD4pTWIBwzcbbsL56kZDxRGsF0SsB0VR/jSMY HdI71RgjpQFSyar1rcCTPCRP97KnUC+oaKhn+i2jBMSRxs94GEOqk4LuKNo39HKP tXEMkYl0o/CR9QaFDjncy9M2M3/o50ooBvYTOu0SjmyZO+ab9tJpaXbnlf2ChxJI AWbhBGmwJ6kF5FvVbmzujV7EEF2YCRMBpWo2zjNd6zWvX9OWEOXrOaHuX7iBPCga YqEMQWyS7XWiBG7AI8+ka5x4s/oxWsbn/6pCdDXhfxl5p5jv7ajm7LbLXGut1N6a uV5hmLLgZywF68AYe6X3GWv6mygXMBYABZxEA6klWE7HpIzvLxmxu0+vFlYR8qsb FMAacJ/FYJ9nGRuMqG+V2Edr5U//JvrWqy4raPIvwXGtX+FsqEc= =Zavb -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
