Terence, thanks for your reply! best, Jenny On Sun, Jun 2, 2024 at 3:11 AM Terence M. Bandoian <tere...@tmbsw.com> wrote:
> A long time ago (Tomcat 7), I would see a Tomcat memory leak detection > error on shutdown if the JDBC driver was located in WEB-INF/lib but not > if it was in the Tomcat lib directory. Explicitly de-registering the > driver with a ServletContextListener on shutdown eliminated the error. > I'm not sure if that's still necessary or if it applies in your case. > > -Terence Bandoian > > On 6/2/2024 1:56 AM, Christopher Schultz wrote: > > Jenny, > > > > (Apologies for top-posting) > > > > “Safely ignored” can mean many things. You are only in danger of running > out of heap space. So if you aren’t worried about that, feel free to ignore > the error message. > > > > If it were my system, I would want to ensure a clean unload of the > driver when the application shuts down. > > > > But I don’t think it will harm anything besides your memory usage. > > > > -chris > > > >> On Jun 1, 2024, at 00:18, Ying Jin<jiny4...@gmail.com> wrote: > >> > >> Chris, > >> > >> Thanks for your reply! > >> > >> We already removed the ojdbc8.jar file from the application's > Web-inf/lib > >> folder as suggested in the following post, however, we still got the > >> warning messages below after the application is deployed to the Tomcat 9 > >> server. > >> > >> > https://stackoverflow.com/questions/6981564/why-must-the-jdbc-driver-be-put-in-tomcat-home-lib-folder > >> > >> WARNING: The web application [Our Web Application Name] appears to have > >> started a thread named [InterruptTimer] but has failed to stop it. This > is > >> very likely to create a memory leak. Stack trace of thread: > >> > >> WARNING: The web application [Our Web Application Name] appears to have > >> started a thread named [oracle.jdbc.diagnostics.Diagnostic.CLOCK] but > has > >> failed to stop it. This is very likely to create a memory leak. Stack > trace > >> of thread: > >> > >> I also read some posts saying these warning messages can be safely > ignored > >> if the Tomcat version is greater than 7.0. I'm not sure if this is > correct > >> or not. > >> > >> Please advise, > >> > >> Many thanks! > >> Jenny > >> > >>> On Fri, May 31, 2024 at 3:50 PM Christopher Schultz < > >>> ch...@christopherschultz.net> wrote: > >>> > >>> Jenny, > >>> > >>>> On 5/31/24 14:52, Ying Jin wrote: > >>>> We removed the ojdbc8 driver jar from web-inf/lib from the web > >>>> application and kept the ojdbc8 jar file in the Tomcat/lib folder, but > >>>> we still can see the following memory link warning message whenever we > >>>> redeploy the web application. We use the Tomcat 9 server in the Linux > >>>> environment. > >>> This list strips attachments. Can you re-post with text-only? > >>> > >>>> The other warning message is about the "validateFile Problem with jar > >>>> file /tomcat/lib/jolokia.jar. My question is if we can safely ignore > >>>> these warning messages or not. > >>>> > >>>> It would be great if you can shed some light on this issue. > >>> If the message is something like "driver cannot be unloaded" then check > >>> Tomcat with a debugger or even something like JVisualVM to see how many > >>> WebappClassLoaders you have in memory. > >>> > >>> If the driver causes the web application ClassLoader to be "pinned" in > >>> memory, then it will never be removed and all those classes will > >>> continue to use-up heap space until you restart the JVM. This gets > worse > >>> every time you reload your application without restarting the JVM. The > >>> Manager application web UI can help you diagnose these a little. > >>> > >>> The validation problem with the Jolokia JAR file will depend upon > >>> exactly what it says. I would first get a replacement copy of the > >>> Jolokia JAR file before bothering to try to diagnose it any further. > >>> > >>> -chris > >>> > >>> --------------------------------------------------------------------- > >>> To unsubscribe, e-mail:users-unsubscr...@tomcat.apache.org > >>> For additional commands, e-mail:users-h...@tomcat.apache.org > >>> > >>> > > --------------------------------------------------------------------- > > To unsubscribe, e-mail:users-unsubscr...@tomcat.apache.org > > For additional commands, e-mail:users-h...@tomcat.apache.org > > > >
