Re: Tomcat hangs after a few days!
Shapira, Yoav schrieb: Howdy, catalina.out grows up by adding [INFO] ChannelSocket - -server has been restarted or reset this connection Maybe someone at least ;-) can explain under which circumstances such an error message is produced? Look at the source code to see where the message comes from. As the [INFO] indicates, it's not an error, just an informational message. You can configure commons-logging for tomcat so that these messages do not appear in your log. Yoav Shapira Hi Yoav, thanks for your help! What I do not understand: - Look at the source code to see where the message comes from. I think the [INFO]-lines are produced by tomcat and not by the application. Isn´t that correct? Best regards Volker - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat hangs after a few days!
Howdy, Look at the source code to see where the message comes from. As the [INFO] indicates, it's not an error, just an informational message. You can configure commons-logging for tomcat so that these messages do not appear in your log. Yoav Shapira Hi Yoav, thanks for your help! What I do not understand: - Look at the source code to see where the message comes from. I think the [INFO]-lines are produced by tomcat and not by the application. Isn´t that correct? Yup, that's correct, and I meant the tomcat source code not your app's. Yoav Shapira This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat hangs after a few days!
Howdy, Shapira, Yoav schrieb: Cool verb ;) maybe following hint could be important for you: Nearly ALL persons that make use of FreeBSD do NOT use the - in your words - normal configuration or normal jvms because you get trouble with it under FreeBSD. And whose problem is that? ;) Certainly not tomcat's... I suggest you ask John from Volano what's wrong, or alternatively at least try switching to a more common JVM and isolate the problem and benefit from advice such as that Senor Rees has been trying to give you... Like mentioned before the -QUIT signal does not produce a dump in my case, so what should I do? Use a profiler with thread status output (such as OptimizeIt's ThreadDebugger) to try and determine what goes wrong. It is precisely for these types of scenarios that the thread dump feature was added to the Sun JVM, and similar (more advanced, actually) features are in the J:Rockit JVM. If you got yourself into a situation where you can't use these JVMs or debugging features, it's more work for you unfortunately. catalina.out grows up by adding [INFO] ChannelSocket - -server has been restarted or reset this connection Maybe someone at least ;-) can explain under which circumstances such an error message is produced? Look at the source code to see where the message comes from. As the [INFO] indicates, it's not an error, just an informational message. You can configure commons-logging for tomcat so that these messages do not appear in your log. Yoav Shapira This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat hangs after a few days!
Shapira, Yoav schrieb: Howdy, Threads like these are exasperating ;) It almost definitely is a JVM/threading problem. You've already gone into a far less common configuration than most on this list by using Blackdown and green mode. If you do this, you risk not being able to get much support. I, and I imagine many others, read your original question a few days ago, said in my head Blackdown -- don't know/don't care and deleted it. Hi, maybe following hint could be important for you: Nearly ALL persons that make use of FreeBSD do NOT use the - in your words - normal configuration or normal jvms because you get trouble with it under FreeBSD. Green mode has a lot of advantages over threaded mode under some circumstances - especially when you provide a chat server with a lot of simultaneous connections! I suggest you ask John from Volano what's wrong, or alternatively at least try switching to a more common JVM and isolate the problem and benefit from advice such as that Senor Rees has been trying to give you... Like mentioned before the -QUIT signal does not produce a dump in my case, so what should I do? catalina.out grows up by adding [INFO] ChannelSocket - -server has been restarted or reset this connection Maybe someone at least ;-) can explain under which circumstances such an error message is produced? Thx a lot and regards Volker - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat hangs after a few days!
David Rees schrieb: On Tue, October 7, 2003 1at 1:59 am, Volker sent the following Following problem can be recognized even if the tomcat process is not in sbwait mode: 1) Sending a -QUIT signal to the tomcat process does not stop the process. A -QUIT will not shut down Tomcat, but cause the JVM to dump a stack trace to stdout of all threads. This will be useful when the process hangs up. If the process is not responding to the -QUIT command, the JVM has hung up or you have a lot of threads stuck in a tight loop! Hi Dave, I run the jvm in green mode (recommended by John from Volano for Blackdown Java under FreeBSD!). So the problem should not derive from too many threads! Sending the QUIT-signal does not show any result because stdout is the terminal and that one does not print out anything when I send a -QUIT. It is important to emphasize that the process does not show any reaction related to a -QUIT even when tomcat is running correctly. My original problem is that tomcat hangs up after a while (in that case nothing can be done with signals etc.). But what I wanted to explain in my last posting: Even when tomcat is running correctly (handling the servlet requests) you cannot stop it with shutdown.sh or -QUIT. Shutdown.sh only makes the CPU% increase over 90% and nothing does work anymore. But the tomcat process still is in memory. Only a kill -9 helps. 2) Using shutdown.sh and -QUIT show up the same result: tomcat process still stays in memory but suddenly the CPU value increases about over 90%. Only a kill -9 stops the process! With tomcat 3.x I did not have such a problem and I could shutdown tomcat without any problems. Without knowing if and where Tomcat is hung up by reviewing the stack dump, we won't be able to get much further. Like mentioned above: -QUIT does NOT produce any stack dump on the stdout! Thanks Volker -Dave - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat hangs after a few days!
On Wed, October 8, 2003 1at 2:07 am, Volker sent the following David Rees schrieb: On Tue, October 7, 2003 1at 1:59 am, Volker sent the following Following problem can be recognized even if the tomcat process is not in sbwait mode: 1) Sending a -QUIT signal to the tomcat process does not stop the process. A -QUIT will not shut down Tomcat, but cause the JVM to dump a stack trace to stdout of all threads. This will be useful when the process hangs up. If the process is not responding to the -QUIT command, the JVM has hung up or you have a lot of threads stuck in a tight loop! I run the jvm in green mode (recommended by John from Volano for Blackdown Java under FreeBSD!). So the problem should not derive from too many threads! You can suffer from scheduler starvation if you get too many threads running in a tight loop! (I know, it's happenned to me with a green JVM!) Symptoms will be 100% CPU, and the JVM will not respond except to the kill signal. Sending the QUIT-signal does not show any result because stdout is the terminal and that one does not print out anything when I send a -QUIT. It is important to emphasize that the process does not show any reaction related to a -QUIT even when tomcat is running correctly. My original problem is that tomcat hangs up after a while (in that case nothing can be done with signals etc.). But what I wanted to explain in my last posting: Even when tomcat is running correctly (handling the servlet requests) you cannot stop it with shutdown.sh or -QUIT. Shutdown.sh only makes the CPU% increase over 90% and nothing does work anymore. But the tomcat process still is in memory. Only a kill -9 helps. It's been a while since I've used Blackdown's JVM, but if we can't get a stack trace from it when Tomcat is hung up (looks like it's easy for you to reproduce by simply trying to shutdown), it will be difficult to figure out what's going on. Like mentioned above: -QUIT does NOT produce any stack dump on the stdout! On all Sun JVMs (IBM, too?), sending the JVM the QUIT signal will result in a stack trace like the one described here: http://developer.java.sun.com/developer/technicalArticles/Programming/Stacktrace/ It is the easiest way for us to remote debug an issue like this. BTW, does this hang occur with a stock tomcat with only the default webapps running (IE, no changes to the shipped configuration?) -Dave - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat hangs after a few days!
Howdy, Threads like these are exasperating ;) It almost definitely is a JVM/threading problem. You've already gone into a far less common configuration than most on this list by using Blackdown and green mode. If you do this, you risk not being able to get much support. I, and I imagine many others, read your original question a few days ago, said in my head Blackdown -- don't know/don't care and deleted it. I suggest you ask John from Volano what's wrong, or alternatively at least try switching to a more common JVM and isolate the problem and benefit from advice such as that Senor Rees has been trying to give you... Yoav Shapira Millennium ChemInformatics -Original Message- From: David Rees [mailto:[EMAIL PROTECTED] Sent: Wednesday, October 08, 2003 3:51 AM To: Tomcat Users List Subject: Re: Tomcat hangs after a few days! On Wed, October 8, 2003 1at 2:07 am, Volker sent the following David Rees schrieb: On Tue, October 7, 2003 1at 1:59 am, Volker sent the following Following problem can be recognized even if the tomcat process is not in sbwait mode: 1) Sending a -QUIT signal to the tomcat process does not stop the process. A -QUIT will not shut down Tomcat, but cause the JVM to dump a stack trace to stdout of all threads. This will be useful when the process hangs up. If the process is not responding to the -QUIT command, the JVM has hung up or you have a lot of threads stuck in a tight loop! I run the jvm in green mode (recommended by John from Volano for Blackdown Java under FreeBSD!). So the problem should not derive from too many threads! You can suffer from scheduler starvation if you get too many threads running in a tight loop! (I know, it's happenned to me with a green JVM!) Symptoms will be 100% CPU, and the JVM will not respond except to the kill signal. Sending the QUIT-signal does not show any result because stdout is the terminal and that one does not print out anything when I send a -QUIT. It is important to emphasize that the process does not show any reaction related to a -QUIT even when tomcat is running correctly. My original problem is that tomcat hangs up after a while (in that case nothing can be done with signals etc.). But what I wanted to explain in my last posting: Even when tomcat is running correctly (handling the servlet requests) you cannot stop it with shutdown.sh or -QUIT. Shutdown.sh only makes the CPU% increase over 90% and nothing does work anymore. But the tomcat process still is in memory. Only a kill -9 helps. It's been a while since I've used Blackdown's JVM, but if we can't get a stack trace from it when Tomcat is hung up (looks like it's easy for you to reproduce by simply trying to shutdown), it will be difficult to figure out what's going on. Like mentioned above: -QUIT does NOT produce any stack dump on the stdout! On all Sun JVMs (IBM, too?), sending the JVM the QUIT signal will result in a stack trace like the one described here: http://developer.java.sun.com/developer/technicalArticles/Programming/S tack trace/ It is the easiest way for us to remote debug an issue like this. BTW, does this hang occur with a stock tomcat with only the default webapps running (IE, no changes to the shipped configuration?) -Dave - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat hangs after a few days!
David Rees schrieb: Can you send the Tomcat process a -QUIT signal so we can see what the state of the JVM is? It sounds like a JVM bug, and Java on FreeBSD is less than heavily used... Try a different JVM if you can. Hi David, I use the most stable jvm I know for FreeBSD: Blackdown Java under Linux Emulation Mode. Following problem can be recognized even if the tomcat process is not in sbwait mode: 1) Sending a -QUIT signal to the tomcat process does not stop the process. 2) Using shutdown.sh and -QUIT show up the same result: tomcat process still stays in memory but suddenly the CPU value increases about over 90%. Only a kill -9 stops the process! With tomcat 3.x I did not have such a problem and I could shutdown tomcat without any problems. Any idea? Thanks and regards Volker - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat hangs after a few days!
On Tue, October 7, 2003 1at 1:59 am, Volker sent the following Following problem can be recognized even if the tomcat process is not in sbwait mode: 1) Sending a -QUIT signal to the tomcat process does not stop the process. A -QUIT will not shut down Tomcat, but cause the JVM to dump a stack trace to stdout of all threads. This will be useful when the process hangs up. If the process is not responding to the -QUIT command, the JVM has hung up or you have a lot of threads stuck in a tight loop! 2) Using shutdown.sh and -QUIT show up the same result: tomcat process still stays in memory but suddenly the CPU value increases about over 90%. Only a kill -9 stops the process! With tomcat 3.x I did not have such a problem and I could shutdown tomcat without any problems. Without knowing if and where Tomcat is hung up by reviewing the stack dump, we won't be able to get much further. -Dave - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Tomcat hangs after a few days!
Hi, I already posted following question on 26th Sep but the replies did not refer to my problem but another one. Maybe someone has a helpful hint for me!? Thx Volker - I have a problem running Jakarta Tomcat 4.1 port under FreeBSD 4.4 with Blackdown Java 1.3.1 with mod_jk 1.2: After startup.sh /logs/catalina.out shows up following lines: [INFO] Registry - -Loading registry information [INFO] Registry - -Creating new Registry instance [INFO] Registry - -Creating MBeanServer [INFO] Http11Protocol - -Initializing Coyote HTTP/1.1 on port 8080 Starting service Tomcat-Standalone Apache Tomcat/4.1.24 HTTP Tunnel connected to the DigiChat server localhost HttpTunnelingServlet connected to the groopz server [INFO] Http11Protocol - -Starting Coyote HTTP/1.1 on port 8080 [INFO] ChannelSocket - -JK2: ajp13 listening on 0.0.0.0/0.0.0.0:8009 [INFO] JkMain - -Jk running ID=0 time=7/21 config=/usr/local/jakarta-tomcat4.1/conf/jk2.properties [INFO] ChannelSocket - -server has been restarted or reset this connection [INFO] ChannelSocket - -server has been restarted or reset this connection [INFO] ChannelSocket - -server has been restarted or reset this connection [INFO] ChannelSocket - -server has been restarted or reset this connection The first days everythings runs correctly. The example servlets can be executed via port 80 by help of mod_jk. After a few days suddenly the servlets cannot be executed anymore. Having a look on the Tomcat process with top prints out state sbwait. That state does not change anymore AND I cannot shutdown the tomcat process by help of shutdown.sh - so I have to kill the process with kill -9. catalina.out meanwhile has grown up to nearly 1MB because a lot of lines (content: [INFO] ChannelSocket - -server has been restarted or reset this connection ) have been inserted. Killing and restarting Tomcat manually and restarting apache afterwards for activating mod_jk again results in making all work again. Does anyone have an idea of what is happening here? Thanks and regards Volker - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat hangs after a few days!
Can you send the Tomcat process a -QUIT signal so we can see what the state of the JVM is? It sounds like a JVM bug, and Java on FreeBSD is less than heavily used... Try a different JVM if you can. -Dave On Mon, October 6, 2003 at 6:37 am, Volker sent the following Hi, I already posted following question on 26th Sep but the replies did not refer to my problem but another one. Maybe someone has a helpful hint for me!? Thx Volker - I have a problem running Jakarta Tomcat 4.1 port under FreeBSD 4.4 with Blackdown Java 1.3.1 with mod_jk 1.2: - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
