-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Louis,
On 9/26/18 15:56, Louis Zipes wrote: > Problem just re-occurred and so I was able to at least get a JSTACK > (I assume it was Tomcat since it was the Java using the most memory > on the machine). Here is the reoccurring message. I get more hits > on but haven't dug through all of the Google hits yet (due to > multi-tasking) so apologies up front if there is a simple answer to > this. > > "Event_Manager_1413" daemon prio=6 tid=0x0000000024856000 > nid=0x40c4 waiting on condition [0x0000000042dae000] > java.lang.Thread.State: TIMED_WAITING (parking) at > sun.misc.Unsafe.park(Native Method) - parking to wait for > <0x00000005ab45f7b8> (a > java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject) > > at java.util.concurrent.locks.LockSupport.parkNanos(Unknown Source) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject. awaitNanos(Unknown > Source) at java.util.concurrent.LinkedBlockingQueue.poll(Unknown > Source) at java.util.concurrent.ThreadPoolExecutor.getTask(Unknown > Source) at > java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) > at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown > Source) at java.lang.Thread.run(Unknown Source) This thread is waiting for a task, and is essentially idle. You will have many of these on a non-busy system. What are the other threads doing? > Locked ownable synchronizers: - None > >> 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. > > I'm using the ojdbc6.jar if that is what you are referring to or is > there a better setting somewhere. ODBC? What is your database? - -chris > -----Original Message----- From: Christopher Schultz > [mailto:ch...@christopherschultz.net] Sent: Wednesday, September > 26, 2018 3:46 PM To: users@tomcat.apache.org Subject: Re: > Application hanging on Tomcat 7.0.54 > > - - - external message, proceed with caution - - - > > > 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-shutdo w > >> 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 > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > > --------------------------------------- CONFIDENTIALITY NOTICE: > This message is for intended addressee(s) only and may contain > information that is confidential, proprietary or exempt from > disclosure. If you are not the intended recipient, please contact > the sender immediately. Unauthorized use or distribution is > prohibited and may be unlawful. > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Thunderbird - https://www.enigmail.net/ iQIzBAEBCAAdFiEEMmKgYcQvxMe7tcJcHPApP6U8pFgFAlusFlwACgkQHPApP6U8 pFi1oRAAiPywkBdpBqHBKpxkSS4n7/3X6fKH67ZHHbL4XUVS/3T7CNLwm7LXfWcE K4+un6R8ghhaUUtok40PZPi1yC3bNcya2ON/kG7lFPP0WLXnNRUDjNo3gkbjfY+J eu3pgTiPdZmjvvlzsvuXWAMihwXcB5isNYSq3Xsmz30i5w84dbfT4myNZUFMDNZT jb7TCrrZ0UzrKEYmgSoPUC66R4ckWZAP7H4+Hf33IT23TwAcWPWD+jDhqTrdD3mE m30digNNVWbb4D1IbPbk/S+YYCh9UOHys8WvBw9sYW3+IdCkfwj3EjlSeiBC7mNj HHTYFODalBBPPWTaaeXtLMQuPWXYPASUTUnZOVFGeuNEyicqyhWS54nJB+MglkT2 pWaM0guPjmF3ivpCIdkyHjJB0tFW4/FTPMaywET26N2j5Xw5hH+4iP9GlwGcDMA9 yXJs+QeaP8nvuG7zgSmq+N6nojJBne3VZR2aZT/rgakJu1eP9HywVtE3URWZy4Ur FJUYzsRLtvAIIBRhJSQNVuIvlmMp5V0QRBfPYRh7gPnBpFJQGmBoVORbVOKxysfu 2WMpBVGPJrsXG92hvuyK1o/S9zAadTsWqUTJ3nGlRx4bbPl3NCZqXB0RRTLJe1yb xcBSwfMYHmxBTCpajFqLdMSEkGpDUJNf+NZ90+h7m7rGjSSoSug= =X6UE -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
