Re: Memory Usage - Tomcat 5.0.25
Nandish Rudra wrote: Hello Everyone, I am writing about this error from yesterday. I used JProfiler to monitor my memory usage. And am now sure that each and every static object is trashed when the application is undeployed and the profiler shows that memory is free and all instance of the objects are GC'd. This works on a Windows 2000 setup of Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1, but fails miserably on GNU Linux 2.4.20-8 setup. this happens with both tomcat 5.0.25 and 5.0.27 Any ideas why something like this could be happening. Nandish Rudra ECI Conference call Service LLC. -Original Message- From: Shapira, Yoav [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:35 PM To: Tomcat Users List Subject: RE: Memory Usage - Tomcat 5.0.25 Hi, I have a couple of ideas. One is that your webapp maintain static or shared references to objects that prevent them from being garbage collected, and therefore memory from returning to the heap. Another is that a webapp undeploy is not guaranteed to reclaim all memory used by the webapp anyways so to count on this behavior is not smart. It is expected that every time you reload your webapp the overall memory usage of the server will go up a bit, as not all objects are gone (for example, if you have a static reference than the old classloader and anything that references it strongly will remain in memory). Yoav Shapira Millennium Research Informatics -Original Message- From: Nandish Rudra [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:17 PM To: Tomcat Users List (E-mail) Subject: Memory Usage - Tomcat 5.0.25 Hello, I am having some memory issues while deploing/undeploying web applications to Tomcat. I am using Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1 on GNU Linux 2.4.20-8. I use ant to compile my web application and Tomcat's catalina-ant.jar to deploy it automatically. Here is my problem. When I undeploy/remove an application, Tomcat does not reclaim the memory being used by the web application and when the application is re-deployed/re-installed a significant increase in memory is seen. This increase is obviously the memory usage by the new instance of the web application. Does anyone have any idea as to why this is happening? Try looking at jvmstat (http://developers.sun.com/dev/coolstuff/jvmstat/) My own tests with show that its the permanent space of objects that gets filled up and not reclaimed after each reload. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Memory Usage - Tomcat 5.0.25
Hi, LONG-snip / Does anyone have any idea as to why this is happening? Try looking at jvmstat (http://developers.sun.com/dev/coolstuff/jvmstat/) My own tests with show that its the permanent space of objects that gets filled up and not reclaimed after each reload. Yup, that's as expected. Yoav Shapira - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: FW: Memory Usage - Tomcat 5.0.25
Hi, Yes the objects are GC'd but memory stays. If you look through yesterday's posts you will see emails that helped me solve the issue on Windows machine, but the issue is still alive with RedHat 9.0. I am in the process probing the linux boex's mepry to see what the is going on. Nandish Rudra ECI Conference Call Services, LLC -Original Message- From: Joseph Shraibman [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 11, 2004 8:54 PM To: Tomcat Users List Subject: Re: FW: Memory Usage - Tomcat 5.0.25 Nandish Rudra wrote: Hello Everyone, I am writing about this error from yesterday. I used JProfiler to monitor my memory usage. And am now sure that each and every static object is trashed when the application is undeployed and the profiler shows that memory is free and all instance of the objects are GC'd. This works on a Windows 2000 setup of Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1, but fails miserably on RedHat 9 setup. this happens with both tomcat 5.0.25 and 5.0.27 I'm a bit confused. Are you saying that the objects are GC'd on redhat 9 but the jvm is still big, or are you saying that the objects were never GC'd? - 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: FW: Memory Usage - Tomcat 5.0.25
What memory are you looking at, what ps returns? What does Runtime.freeMemory() and Runtime.totalMemory() return? Nandish Rudra wrote: Hi, Yes the objects are GC'd but memory stays. If you look through yesterday's posts you will see emails that helped me solve the issue on Windows machine, but the issue is still alive with RedHat 9.0. I am in the process probing the linux boex's mepry to see what the is going on. Nandish Rudra ECI Conference Call Services, LLC -Original Message- From: Joseph Shraibman [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 11, 2004 8:54 PM To: Tomcat Users List Subject: Re: FW: Memory Usage - Tomcat 5.0.25 Nandish Rudra wrote: Hello Everyone, I am writing about this error from yesterday. I used JProfiler to monitor my memory usage. And am now sure that each and every static object is trashed when the application is undeployed and the profiler shows that memory is free and all instance of the objects are GC'd. This works on a Windows 2000 setup of Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1, but fails miserably on RedHat 9 setup. this happens with both tomcat 5.0.25 and 5.0.27 I'm a bit confused. Are you saying that the objects are GC'd on redhat 9 but the jvm is still big, or are you saying that the objects were never GC'd? - 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] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: FW: Memory Usage - Tomcat 5.0.25
Hello QM, Thanks for your reply, it really cleared some things. First, tomcat has two levels for memory - allocated vs. used. While allocated increases with every spike by some amout and stays there, the used memor fluctuates. If I set the memory bounds for JVM by the mechanism you have said than once the allocated reaches that level, tomcat will crash(out of memory exception). Now, since all of the allcotaed memory is not being used, is there a way to control the allocated memory, as in, make it fluctuate with used memory. Regards, Nandish Rudra ECI Conference Call Services, LLC -Original Message- From: QM [mailto:[EMAIL PROTECTED] Sent: Tuesday, August 10, 2004 8:38 PM To: Tomcat Users List Subject: Re: FW: Memory Usage - Tomcat 5.0.25 On Tue, Aug 10, 2004 at 04:54:26PM -0400, Nandish Rudra wrote: : I am writing about this error from yesterday. I used JProfiler to monitor my : memory usage. And am now sure that each and every static object is trashed : when the application is undeployed and the profiler shows that memory is : free and all instance of the objects are GC'd. Something else to consider: the memory for the JVM process isn't just the heap. The process maintains some memory for itself, outside of the designated heap ranges set with -Xmx and -Xms, for housekeeping and such. (This is often news to even experienced J2EE developers.) That may very well be what you're seeing. -QM -- software -- http://www.brandxdev.net tech news -- http://www.RoarNetworX.com - 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: FW: Memory Usage - Tomcat 5.0.25
Hello guys, I have finally figured how to make JVM work the way I want it to. Setting some of the following options helps control the allocated memory size by huge amounts. I would strongly recommend using them. echo Setting JAVA_OPTS set JAVA_OPTS=-Xmn32M -Xmx128M -XX:MaxHeapFreeRatio=30 -XX:+UseParallelGC echo Using JAVA_OPTS: %JAVA_OPTS% Related link would be : http://java.sun.com/docs/hotspot/VMOptions.html Now the problem is these work on a Windows box when placed in catalina.bat but fail on a redHat 9 (Kernel 2.4.20-8)machine, in two ways - 1. When I place it in catalina.sh tomcat fails to start. 3. When I place startup.sh, tomcat starts but the windows behavior is not imitated. Any suggestion, Nandish Rudra ECI Conference Call Services, LLC -Original Message- From: Nandish Rudra [mailto:[EMAIL PROTECTED] Sent: Wednesday, August 11, 2004 11:09 AM To: 'Tomcat Users List' Subject: RE: FW: Memory Usage - Tomcat 5.0.25 Hello QM, Thanks for your reply, it really cleared some things. First, tomcat has two levels for memory - allocated vs. used. While allocated increases with every spike by some amout and stays there, the used memor fluctuates. If I set the memory bounds for JVM by the mechanism you have said than once the allocated reaches that level, tomcat will crash(out of memory exception). Now, since all of the allcotaed memory is not being used, is there a way to control the allocated memory, as in, make it fluctuate with used memory. Regards, Nandish Rudra ECI Conference Call Services, LLC -Original Message- From: QM [mailto:[EMAIL PROTECTED] Sent: Tuesday, August 10, 2004 8:38 PM To: Tomcat Users List Subject: Re: FW: Memory Usage - Tomcat 5.0.25 On Tue, Aug 10, 2004 at 04:54:26PM -0400, Nandish Rudra wrote: : I am writing about this error from yesterday. I used JProfiler to monitor my : memory usage. And am now sure that each and every static object is trashed : when the application is undeployed and the profiler shows that memory is : free and all instance of the objects are GC'd. Something else to consider: the memory for the JVM process isn't just the heap. The process maintains some memory for itself, outside of the designated heap ranges set with -Xmx and -Xms, for housekeeping and such. (This is often news to even experienced J2EE developers.) That may very well be what you're seeing. -QM -- software -- http://www.brandxdev.net tech news -- http://www.RoarNetworX.com - 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] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: FW: Memory Usage - Tomcat 5.0.25
Nandish Rudra wrote: Hello Everyone, I am writing about this error from yesterday. I used JProfiler to monitor my memory usage. And am now sure that each and every static object is trashed when the application is undeployed and the profiler shows that memory is free and all instance of the objects are GC'd. This works on a Windows 2000 setup of Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1, but fails miserably on RedHat 9 setup. this happens with both tomcat 5.0.25 and 5.0.27 I'm a bit confused. Are you saying that the objects are GC'd on redhat 9 but the jvm is still big, or are you saying that the objects were never GC'd? - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Memory Usage - Tomcat 5.0.25
Hello Everyone, I am writing about this error from yesterday. I used JProfiler to monitor my memory usage. And am now sure that each and every static object is trashed when the application is undeployed and the profiler shows that memory is free and all instance of the objects are GC'd. This works on a Windows 2000 setup of Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1, but fails miserably on GNU Linux 2.4.20-8 setup. this happens with both tomcat 5.0.25 and 5.0.27 Any ideas why something like this could be happening. Nandish Rudra ECI Conference call Service LLC. -Original Message- From: Shapira, Yoav [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:35 PM To: Tomcat Users List Subject: RE: Memory Usage - Tomcat 5.0.25 Hi, I have a couple of ideas. One is that your webapp maintain static or shared references to objects that prevent them from being garbage collected, and therefore memory from returning to the heap. Another is that a webapp undeploy is not guaranteed to reclaim all memory used by the webapp anyways so to count on this behavior is not smart. It is expected that every time you reload your webapp the overall memory usage of the server will go up a bit, as not all objects are gone (for example, if you have a static reference than the old classloader and anything that references it strongly will remain in memory). Yoav Shapira Millennium Research Informatics -Original Message- From: Nandish Rudra [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:17 PM To: Tomcat Users List (E-mail) Subject: Memory Usage - Tomcat 5.0.25 Hello, I am having some memory issues while deploing/undeploying web applications to Tomcat. I am using Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1 on GNU Linux 2.4.20-8. I use ant to compile my web application and Tomcat's catalina-ant.jar to deploy it automatically. Here is my problem. When I undeploy/remove an application, Tomcat does not reclaim the memory being used by the web application and when the application is re-deployed/re-installed a significant increase in memory is seen. This increase is obviously the memory usage by the new instance of the web application. Does anyone have any idea as to why this is happening? Regards, NR - 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] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
FW: Memory Usage - Tomcat 5.0.25
Hello Everyone, I am writing about this error from yesterday. I used JProfiler to monitor my memory usage. And am now sure that each and every static object is trashed when the application is undeployed and the profiler shows that memory is free and all instance of the objects are GC'd. This works on a Windows 2000 setup of Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1, but fails miserably on RedHat 9 setup. this happens with both tomcat 5.0.25 and 5.0.27 Any ideas why something like this could be happening. Nandish Rudra ECI Conference call Service LLC. -Original Message- From: Shapira, Yoav [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:35 PM To: Tomcat Users List Subject: RE: Memory Usage - Tomcat 5.0.25 Hi, I have a couple of ideas. One is that your webapp maintain static or shared references to objects that prevent them from being garbage collected, and therefore memory from returning to the heap. Another is that a webapp undeploy is not guaranteed to reclaim all memory used by the webapp anyways so to count on this behavior is not smart. It is expected that every time you reload your webapp the overall memory usage of the server will go up a bit, as not all objects are gone (for example, if you have a static reference than the old classloader and anything that references it strongly will remain in memory). Yoav Shapira Millennium Research Informatics -Original Message- From: Nandish Rudra [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:17 PM To: Tomcat Users List (E-mail) Subject: Memory Usage - Tomcat 5.0.25 Hello, I am having some memory issues while deploing/undeploying web applications to Tomcat. I am using Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1 on GNU Linux 2.4.20-8. I use ant to compile my web application and Tomcat's catalina-ant.jar to deploy it automatically. Here is my problem. When I undeploy/remove an application, Tomcat does not reclaim the memory being used by the web application and when the application is re-deployed/re-installed a significant increase in memory is seen. This increase is obviously the memory usage by the new instance of the web application. Does anyone have any idea as to why this is happening? Regards, NR - 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] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: FW: Memory Usage - Tomcat 5.0.25
On Tue, Aug 10, 2004 at 04:54:26PM -0400, Nandish Rudra wrote: : I am writing about this error from yesterday. I used JProfiler to monitor my : memory usage. And am now sure that each and every static object is trashed : when the application is undeployed and the profiler shows that memory is : free and all instance of the objects are GC'd. Something else to consider: the memory for the JVM process isn't just the heap. The process maintains some memory for itself, outside of the designated heap ranges set with -Xmx and -Xms, for housekeeping and such. (This is often news to even experienced J2EE developers.) That may very well be what you're seeing. -QM -- software -- http://www.brandxdev.net tech news -- http://www.RoarNetworX.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Memory Usage - Tomcat 5.0.25
Hello, I am having some memory issues while deploing/undeploying web applications to Tomcat. I am using Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1 on GNU Linux 2.4.20-8. I use ant to compile my web application and Tomcat's catalina-ant.jar to deploy it automatically. Here is my problem. When I undeploy/remove an application, Tomcat does not reclaim the memory being used by the web application and when the application is re-deployed/re-installed a significant increase in memory is seen. This increase is obviously the memory usage by the new instance of the web application. Another important detail to note is that, this behaviour is not seen, in a same setup, on a Windows 2000 machine. Does anyone have any idea as to why this is happening? Regards, NR - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Memory Usage - Tomcat 5.0.25
Hello, I am having some memory issues while deploing/undeploying web applications to Tomcat. I am using Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1 on GNU Linux 2.4.20-8. I use ant to compile my web application and Tomcat's catalina-ant.jar to deploy it automatically. Here is my problem. When I undeploy/remove an application, Tomcat does not reclaim the memory being used by the web application and when the application is re-deployed/re-installed a significant increase in memory is seen. This increase is obviously the memory usage by the new instance of the web application. Does anyone have any idea as to why this is happening? Regards, NR - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Memory Usage - Tomcat 5.0.25
It took the message a while to showup on the list so resent it with some modification. please disregard the first message. The problem does happen on Windows. I was looking at the wrong process. NR - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Memory Usage - Tomcat 5.0.25
Hi, I have a couple of ideas. One is that your webapp maintain static or shared references to objects that prevent them from being garbage collected, and therefore memory from returning to the heap. Another is that a webapp undeploy is not guaranteed to reclaim all memory used by the webapp anyways so to count on this behavior is not smart. It is expected that every time you reload your webapp the overall memory usage of the server will go up a bit, as not all objects are gone (for example, if you have a static reference than the old classloader and anything that references it strongly will remain in memory). Yoav Shapira Millennium Research Informatics -Original Message- From: Nandish Rudra [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:17 PM To: Tomcat Users List (E-mail) Subject: Memory Usage - Tomcat 5.0.25 Hello, I am having some memory issues while deploing/undeploying web applications to Tomcat. I am using Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1 on GNU Linux 2.4.20-8. I use ant to compile my web application and Tomcat's catalina-ant.jar to deploy it automatically. Here is my problem. When I undeploy/remove an application, Tomcat does not reclaim the memory being used by the web application and when the application is re-deployed/re-installed a significant increase in memory is seen. This increase is obviously the memory usage by the new instance of the web application. Does anyone have any idea as to why this is happening? Regards, NR - 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: Memory Usage - Tomcat 5.0.25
Hello Yaov, You are correct I do have a few static varibles that point to running threads and some other objects. When the application is shutdown I ensure that each thread is destroyed and all static varibales are set to null, including thread identifiers, this should let my call to GC clear the memory. You are also right in saying that i should not depend on undeploy to reclaim all memory that the webapp was using, and I don't. Like I mentioned I do make sure all static variables get set to null before the application shuts down. It would be understandable if not all memory utilized by the webapp is reclaimed, but in my case absolutely no memory is being reclaimed. For example, say, i start tomcat and it starts with 30M initial memory usage without the application. Now when i deploy the application the size jumps by 8M to 38M. As the app is undeploy and re-deploy the memory usage jumps from 38M to 46-47M. Now this, if I am not wrong, is not how things should be. I would appreciate anymore suggestion that you or anyone may have. Regards, Nandish -Original Message- From: Shapira, Yoav [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:35 PM To: Tomcat Users List Subject: RE: Memory Usage - Tomcat 5.0.25 Hi, I have a couple of ideas. One is that your webapp maintain static or shared references to objects that prevent them from being garbage collected, and therefore memory from returning to the heap. Another is that a webapp undeploy is not guaranteed to reclaim all memory used by the webapp anyways so to count on this behavior is not smart. It is expected that every time you reload your webapp the overall memory usage of the server will go up a bit, as not all objects are gone (for example, if you have a static reference than the old classloader and anything that references it strongly will remain in memory). Yoav Shapira Millennium Research Informatics -Original Message- From: Nandish Rudra [mailto:[EMAIL PROTECTED] Sent: Monday, August 09, 2004 1:17 PM To: Tomcat Users List (E-mail) Subject: Memory Usage - Tomcat 5.0.25 Hello, I am having some memory issues while deploing/undeploying web applications to Tomcat. I am using Tomcat 5.0.25 with Java 2 SDK version 1.4.2_04 and Ant 1.6.1 on GNU Linux 2.4.20-8. I use ant to compile my web application and Tomcat's catalina-ant.jar to deploy it automatically. Here is my problem. When I undeploy/remove an application, Tomcat does not reclaim the memory being used by the web application and when the application is re-deployed/re-installed a significant increase in memory is seen. This increase is obviously the memory usage by the new instance of the web application. Does anyone have any idea as to why this is happening? Regards, NR - 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] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
