Hi all it seems there is a raise condition when realizing lazy loaded services.
The race is between JustInTimeObjectCreator.obtainObjectFromCreator / ConcurrentBarrier and requires a shared service. When a proxy is instantiated JustInTimeObjectCreator.createObject is called which is synchronized. Eventually this method will call ModuleImpl.findOrCreate which will first acquire a global read lock (ConcurrentBarrier.withRead) to check if the service is available and if not it will acquire a global write lock (ConcurrentBarrier.withWrite) and finally instantiate. An example that will deadlock is the following Thread A 1. Calls a method from service A 2. JustInTimeObjectCreator.createObject of service A called 3. ConcurrentBarrier.withRead called 4. ConcurrentBarrier.withWrite called 5. Service A constructor called 6. On the constructor we call a method from Service B 7. JustInTimeObjectCreator.createObject of Service B called 8. Cannot proceed since its waiting from synchronization of Thread B (See below) JustInTimeObjectCreator.createObject to complete Thread B (comes after step 3 of thread A) 1. Calls a method from service B 2. JustInTimeObjectCreator.createObject of service B called 3. ConcurrentBarrier.withRead called cannot proceed due to being locked from Thread A I managed to find two issues reported already with the exact same issue 1. https://www.mail-archive.com/users@tapestry.apache.org/msg77239.html 2. https://mail-archives.apache.org/mod_mbox/tapestry-users/201310.mbox/browser Thanks
