Hi! Well I am also getting the same out of memory errors, FI: I am using Oracle database. I found some info that talks about setting time-out for DB Con Poolng. Will start with this info and see how it helps. Pasting the info below for any further analysis and comments by the grp:
"Tomcat runs within a JVM. The JVM periodically performs garbage collection (GC) to remove java objects which are no longer being used. When the JVM performs GC execution of code within Tomcat freezes. If the maximum time configured for establishment of a dB connection is less than the amount of time garbage collection took you can get a db conneciton failure. To collect data on how long garbage collection is taking add the -verbose:gc argument to your CATALINA_OPTS environment variable when starting Tomcat.When verbose gc is enabled your $CATALINA_BASE/logs/catalina.out log file will include data for every garbage collection including how long it took.When your JVM is tuned correctly 99% of the time a GC will take less than one second. The remainder will only take a few seconds. Rarely, if ever should a GC take more than 10 seconds.Make sure that the db connection timeout is set to 10-15 seconds. For the DBCP you set this using the parameter maxWait." Thanks, Rommel. -----Original Message----- From: Hari Venkatesan [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 23, 2003 8:00 PM To: Tomcat Users List Subject: RE: Memory Mgmt Tomcat Shapira, I don't think the question is ridiculous. There are a lot of people out there who have implemented tomcat in production environment and we as starters would like to know how they managed some of the delicate issues like this. Off late there have been many queries about memory management and the reason behind this is because people get bombarded with "out of memory error". Personally, I have been researching the same problem for almost a week now, still without any right answers even after searching the archives. Different JVM's do memory management in its own way and that is even more confusing. You start tomcat with -verbose:gc, you can see GC kicks in even as it starts. From what I learnt from java.sun.com, a full GC kicks in only after it reaches its max heap. But you can see Full GC's in the verbose output even before the JVM reaching its max heap. This makes you believe that something is wrong somewhere and that is when people come out here to post their question to get some light from experienced users of tomcat. By the way I have gone through the entire archive about this topic and none of them give a final answer. Hari -----Original Message----- From: Rommel Sharma [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 23, 2003 9:20 AM To: Tomcat Users List Subject: RE: Memory Mgmt Tomcat Thanks! Thats the lead I was looking for... -----Original Message----- From: Shapira, Yoav [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 23, 2003 7:37 PM To: Tomcat Users List Subject: RE: Memory Mgmt Tomcat Howdy, The reason no one answered your original question is because it's kind of ridiculous ;) I don't mean that in an offensive way. I do mean: - Java has its own garbage collector. Tomcat doesn't need to implement its own. There is much information on this topic on java.sun.com and other general java forums. - Many many many threads have gone on this list regarding garbage collection and how to tune for it. Search the list archives for more details. Yoav Shapira Millennium ChemInformatics >-----Original Message----- >From: Rommel Sharma [mailto:[EMAIL PROTECTED]] >Sent: Thursday, January 23, 2003 9:11 AM >To: Tomcat Users List >Subject: Memory Mgmt Tomcat > >Hi! > I think the answer give to Nate should help, but just in case some one >knows how to do performance tuning of Tomcat when heavy objects are being >used, for effective 'memory management' then please put some light on the >topic. >Thanks, >Rommel. > >-----Original Message----- >From: Shapira, Yoav [mailto:[EMAIL PROTECTED]] >Sent: Thursday, January 23, 2003 7:30 PM >To: Tomcat Users List >Subject: RE: Resources for a Context > > >Howdy, >Can you please illustrate a possible use for this feature before you >start coding it? A use case which can't be addressed by the servlet >spec, that is. Right now, I doubt such a contribution would be accepted >into tomcat's core, so you may not want to waste time writing it at all >;) > >Yoav Shapira >Millennium ChemInformatics > > >>-----Original Message----- >>From: David Keyes [mailto:[EMAIL PROTECTED]] >>Sent: Wednesday, January 22, 2003 5:10 PM >>To: Tomcat Users List >>Subject: RE: Resources for a Context >> >>I would be happy to make any modifications that would be required. >I've >>spent a bit of time looking around at the source already, but I'm not >sure >>what the best approach would be. It would be nice if it could be done >in a >>"plugin" kind of way, but after looking around a bit, it seems that the >>concept of a single physical directory as a docbase is pretty ingrained >>(comments?). >> >>So far, I've looked at the following: >> >>1. Writing a new catalina Context implementation >>2. Writing a new jndi DirContext implementation, that would be >configurable >>to take multiple directories >> >>Of those two, I think #2 makes the most sense, but I have doubts as to >>whether it would solve the problem. What I'm afraid of is that the >changes >>required are peppered throughout the Tomcat codebase. Any pointers >that >>you could give me to get me started in the right direction initially >would >>be hugely appreciated. >> >>The only reason that I'm spending so much energy on this is that for >very >>large web applications that are not structured as a webapp, which I >think >>is rather common, it would be a HUGE aid in debugging to be able to >pull >>something like this off. The code/compile/debug cycle gets a bit >>cumbersome when one is constantly redeploying large apps. I think for >>deployment the spec works just fine. >> >>Thanks again for your help, and all of your excellent work. >> >>Dave Keyes >> >>-----Original Message----- >>From: Craig R. McClanahan [mailto:[EMAIL PROTECTED]] >>Sent: Wednesday, January 22, 2003 4:24 PM >>To: Tomcat Users List >>Subject: RE: Resources for a Context >> >> >> >> >>On Wed, 22 Jan 2003, David Keyes wrote: >> >>> Date: Wed, 22 Jan 2003 15:53:22 -0500 >>> From: David Keyes <[EMAIL PROTECTED]> >>> Reply-To: Tomcat Users List <[EMAIL PROTECTED]> >>> To: Tomcat Users List <[EMAIL PROTECTED]> >>> Subject: RE: Resources for a Context >>> >>> So what mechanism would you suggest for making MORE than one >Resources >>> directory available for a Context? >> >>* Modify Tomcat to support multiple resources directories >> (It's open source :-). Note that you're violating the letter >> and spirit of the servlet spec's requirements on webapp >> organization, so it would be problematic accepting such a >> change back into Tomcat's core. >> >>* Use symbolic links (which doesn't help Windows users much). >> >>* Build deployment scripts that copy everything you need in the webapp >> together. >> >>Craig >> >> >>-- >>To unsubscribe, e-mail: <mailto:tomcat-user- >>[EMAIL PROTECTED]> >>For additional commands, e-mail: <mailto:tomcat-user- >>[EMAIL PROTECTED]> >> >> >>-- >>To unsubscribe, e-mail: <mailto:tomcat-user- >>[EMAIL PROTECTED]> >>For additional commands, e-mail: <mailto:tomcat-user- >>[EMAIL PROTECTED]> > > >-- >To unsubscribe, e-mail: ><mailto:[EMAIL PROTECTED]> >For additional commands, e-mail: ><mailto:[EMAIL PROTECTED]> > > >-- >To unsubscribe, e-mail: <mailto:tomcat-user- >[EMAIL PROTECTED]> >For additional commands, e-mail: <mailto:tomcat-user- >[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
