On 18/04/2016 12:14, Alan Bateman wrote: > On 18/04/2016 10:18, Mark Thomas wrote: >> Hi, >> >> The Apache Tomcat community was asked by Rory O'Donnell for feedback on >> JDK 9 + Project Jigsaw. Having provided that feedback we were directed >> here so I have reproduced that feedback below. >> >> >> I've started testing Tomcat trunk with JDK 9 + Project Jigsaw and it >> looks like we are going to hit a bunch of problems related to Tomcat's >> memory leak protection. >> >> The short version is there are lots of JDK calls that can result in a >> reference being retained to the current class loader. If that class >> loader is the web application class loader it often ends up being pinned >> in memory. This triggers a memory leak when the web application is >> reloaded since the web application class loader is not eligible for GC. >> >> Tomcat generally uses reflection to find these problems. It then does >> one of two things: >> - If the JRE provides an API the application developer should have used >> to clean up the reference, Tomcat does this for them and then logs a >> very loud error message telling the developer they need to fix their app. >> - If there is nothing the developer could have done to avoid the >> problem, Tomcat cleans it up. Usually this is via reflection again. >> >> Reporting this second class of issues as JRE bugs has been on my TODO >> list for a long time. It looks like Java 9 is going to bump this to the >> top of the list. > I remember you brought this up on core-libs-dev [1] and the suggestion > at the time was to create bugs for any of the issues that are still > relevant. So yes, bumping the priority on that would be good. > > On the RMI issue then it would be good to start a thread specifically on > this topic on core-libs-dev.
OK. I'll restart this thread there. I'm also reviewing the various other leaks and I'll start new threads as each one is confirmed. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
