Hi guys, I'm trying to reduce the enormous number of lock done by the current implementation of Embedded Component Manager and I could use some more brains to check what I did. You can find the new version on https://github.com/xwiki/xwiki-commons/blob/feature-improvecm/xwiki-commons… Quick comparison with the current one: * removed all "synchronized (this)" that was in pretty much all the methods and which made the CM block everything whenever anyone was using it * used ConcurrentHashMap to securize the insertion/search of components * basically the only remaining explicit lock is on singleton component initialization mostly to make sure we don't initialize the same component at the same time If you find some small modification to improve a bit the speed don't hesitate too. There is possible improvements to speed up lookuplist and lookupmap (not going though the whole map basically) but it require important refactoring and I would prefer not doing too much things at once since it's a pretty critical peace of code and locking is the main issue right now. Thanks, -- Thomas Mortagne