Re: Tomcat4 performance issue when manually removing compiledjsps in work folder
Peter, I'm getting closer. I installed the latest stable version of Tomcat, copied my web application folder into the tomcat5 webapps folder and this what I have noticed. Any jsp page from the existing web app seems to be getting recompiled and not cached in tomcat. This is what I can't figure out: If I create a new jsp page in the web app and copy the exact source from an existing jsp into the new file (named differently than the existing one), the new jsp is getting cached just fine. When I refresh that page a bunch of times, the response time is instant and my cpu activity stays very low. But when I continue to load any jsp pages from the existing web app, my cpu hits 60%, the response time is slower and they seem to be getting recompiled on every request. Makes no sense, both the new and old jsp page have the same content but the old one seems to keep getting recompiled on every request. Do you have any ideas why Tomcat would be doing this? Thanks again for your help, - Duncan - Original Message - From: Peter Johnson [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Tuesday, March 30, 2004 2:35 AM Subject: Re: Tomcat4 performance issue when manually removing compiledjspsin work folder Duncan, Restarting is like wiping the slate clean in terms of Tomcat's caching in the work directory. So, it is expected that it would take a little while, even just to load the classes in to memory to serve. If you are using JSP I believe that these are always recompiled at start with the class files from the your webapp/WEB-INF/classes and lib directories being loaded in to memory. PJ On Fri, 2004-03-26 at 19:11, Duncan Krebs wrote: Peter, Thanks for the reply. It would make sense that on the request immediately after I delete the .java and .class files in the work folder it would take longer because tomcat has to recompile the jsp's. However even after they are recompiled (not deleted again)and tomcat is restarted subsequent requests continue to take longer and the CPU continues to hit 100%. I wonder if there is a way to analyze the request and see what code is taking so long to execute. - Duncan - Original Message - From: Peter Johnson [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Tuesday, March 30, 2004 2:00 AM Subject: Re: Tomcat4 performance issue when manually removing compiled jspsin work folder Duncan, I believe (and could be wrong) that this is intended behaviour. The work directory is like Tomcat's cache of all the webapps it is currently serving. When a request comes in for a page it tries to serve from this directory, if the class file does not exist it generates the .java files from /webapp and then compiles them so that it can serve them. So, the 3s delay and 100% utilisation is expected because Tomcat is recompiling the files so that it can serve them. PJ On Fri, 2004-03-26 at 18:39, Duncan Krebs wrote: Hi, I have had this snag for some time now and its starting to get the best of me. I'm running tomcat 4.1 and when I manually remove the .java and .class files in the /work/standalone folder even after the initial request of recompiling the jsp's tomcat hits 100% on my CPU and the overall response time is delayed by about 3 seconds on each request. As I deleted different sub folders in the work folder (all within the same web application) the degraded performance was consistent with the different sub folders that I was deleting even after the pages were recompiled. Has anyone experienced this before? All of my requests are going through a Servlet controller and I have a lot of classes in my WEB-INF folder that are part of the framework but I don't think that would have anything to do with this. I've also tried rebuilding my entire project from scratch and I'm still having the same issue of a slowed response time of about 3 seconds and tomcat taking all my CPU. Regards, dkrebs - 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] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat4 performance issue when manually removing compiledjsps in work folder
Could your jsp source files have been modified In the future? -Original Message- From: Duncan Krebs To: Tomcat Users List Sent: 26/03/2004 09:39 Subject: Re: Tomcat4 performance issue when manually removing compiledjsps in work folder Peter, I'm getting closer. I installed the latest stable version of Tomcat, copied my web application folder into the tomcat5 webapps folder and this what I have noticed. Any jsp page from the existing web app seems to be getting recompiled and not cached in tomcat. This is what I can't figure out: If I create a new jsp page in the web app and copy the exact source from an existing jsp into the new file (named differently than the existing one), the new jsp is getting cached just fine. When I refresh that page a bunch of times, the response time is instant and my cpu activity stays very low. But when I continue to load any jsp pages from the existing web app, my cpu hits 60%, the response time is slower and they seem to be getting recompiled on every request. Makes no sense, both the new and old jsp page have the same content but the old one seems to keep getting recompiled on every request. Do you have any ideas why Tomcat would be doing this? Thanks again for your help, - Duncan - Original Message - From: Peter Johnson [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Tuesday, March 30, 2004 2:35 AM Subject: Re: Tomcat4 performance issue when manually removing compiledjspsin work folder Duncan, Restarting is like wiping the slate clean in terms of Tomcat's caching in the work directory. So, it is expected that it would take a little while, even just to load the classes in to memory to serve. If you are using JSP I believe that these are always recompiled at start with the class files from the your webapp/WEB-INF/classes and lib directories being loaded in to memory. PJ On Fri, 2004-03-26 at 19:11, Duncan Krebs wrote: Peter, Thanks for the reply. It would make sense that on the request immediately after I delete the .java and .class files in the work folder it would take longer because tomcat has to recompile the jsp's. However even after they are recompiled (not deleted again)and tomcat is restarted subsequent requests continue to take longer and the CPU continues to hit 100%. I wonder if there is a way to analyze the request and see what code is taking so long to execute. - Duncan - Original Message - From: Peter Johnson [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Tuesday, March 30, 2004 2:00 AM Subject: Re: Tomcat4 performance issue when manually removing compiled jspsin work folder Duncan, I believe (and could be wrong) that this is intended behaviour. The work directory is like Tomcat's cache of all the webapps it is currently serving. When a request comes in for a page it tries to serve from this directory, if the class file does not exist it generates the .java files from /webapp and then compiles them so that it can serve them. So, the 3s delay and 100% utilisation is expected because Tomcat is recompiling the files so that it can serve them. PJ On Fri, 2004-03-26 at 18:39, Duncan Krebs wrote: Hi, I have had this snag for some time now and its starting to get the best of me. I'm running tomcat 4.1 and when I manually remove the .java and .class files in the /work/standalone folder even after the initial request of recompiling the jsp's tomcat hits 100% on my CPU and the overall response time is delayed by about 3 seconds on each request. As I deleted different sub folders in the work folder (all within the same web application) the degraded performance was consistent with the different sub folders that I was deleting even after the pages were recompiled. Has anyone experienced this before? All of my requests are going through a Servlet controller and I have a lot of classes in my WEB-INF folder that are part of the framework but I don't think that would have anything to do with this. I've also tried rebuilding my entire project from scratch and I'm still having the same issue of a slowed response time of about 3 seconds and tomcat taking all my CPU. Regards, dkrebs - 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] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED
Re: Tomcat4 performance issue when manually removing compiledjsps in work folder
On Fri, Mar 26, 2004 at 03:39:13AM -0600, Duncan Krebs wrote: : But when I continue to load any jsp pages from the existing web app, my cpu : hits 60%, the response time is slower and they seem to be getting recompiled : on every request. Makes no sense, both the new and old jsp page have the : same content but the old one seems to keep getting recompiled on every : request. Do you have any ideas why Tomcat would be doing this? That the files have the same content is irrelevant -- Tomcat sees each JSP as a separate entity. The question is, exactly what happens between page refreshes? Are you redeploying your webapp (i.e., overwriting a JSP with the same content, like when you pull the files out of source code control)? Is something else on your machine adjusting the files' timestamps, causing Tomcat to think the file has changed and must thus be rebuilt? fwiw, it's my experience that restarting Tomcat has no effect on the compiled files in the /work dir -- Tomcat will still compare the compiled version to the original. -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]
