On 07/12/2016 15:21, Christopher Schultz wrote: > John, > > On 12/7/16 7:19 AM, John D. Ament wrote: >> On Wed, Dec 7, 2016 at 3:58 AM Mark Thomas <ma...@apache.org> >> wrote: > >>> On 06/12/2016 02:59, John D. Ament wrote: >>> >>> <snip/> >>> >>>> So I was able to identify my issue. It's not specifically a >>>> tomcat problem, but tomcat's bootstrapping makes it unique. >>>> >>>> one of the issues I've observed is that Tomcat's use of >>>> multithreading causes some thread deadlocking with some >>>> synchronized blocks. I was wondering if there's a way to turn >>>> that off? Make tomcat's bootstrap happen in the same thread as >>>> the original invocation? >>> >>> What exactly do you mean by Tomcat's bootstrapping? Can you give >>> an example of concurrent execution that is causing issues? >>> > >> I instantiate the Tomcat object and invoke start() on the "main" >> thread. The invocation of ServletContextListeners happens on a >> "localhost-startStop-1" thread. I would like to have that >> invocation happen on the main thread instead. > > Hmm... there is the "startStopThreads" setting on the Engine, but > unfortunately there is not (currently available) setting that says > "don't use multiple threads at all". It looks like Tomcat is always > going to use at least one (separate) thread to launch the various > Hosts (and webapps).
It wouldn't be too hard to change that to not use an executor if the default of startStopThreads="1" was being used. However... >> Its nothing within tomcat that is deadlocking, but under the covers >> weld has a synchronized block, its inside that synchronized block >> where Tomcat is instantiated. There's a later point where Weld >> tries getting a lock again. In that case, when its single threaded >> (in other containers) it passes since it has a lock, but in this >> case it can't get that lock. The Weld documentation suggests that it is initialized per web application with a ServletContainerInitializer. This would be fine with Tomcat's current use of an Executor for container start/stop. I don't, therefore, understand how Weld is instantiating Tomcat. Can you expand on this? Mark > Is there any way for you to remove the required monitor on your own > code? Or is Weld so intricately-involved in the whole process that > unwinding it isn't possible? > > -chris --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
