On 23 July 2012 01:54, Jeevitha Muthusamy <mail2jeevith...@gmail.com> wrote: > May I know what is Bytecode Caching in AspectJ1.7 and its benefits??
The caching is currently best described here: https://bugs.eclipse.org/bugs/show_bug.cgi?id=367673 It is a per classloader cache of woven bytecode that avoids re-weaving on subsequent restarts. > And when caching is enabled, what exactly is cached?? Per the readme and that bug, the caching is enabled when you turn on the system property: -Daj.weaving.cache.enabled=true The woven bytecode is cached on a per classloader basis. On a subsequent JVM restart the cached woven bytecode will be used instead of repeating the weaving process. > What is the life of Caching? Is it automatically refreshed or is Static? It is not a super intelligent cache. If the incoming classes change (in length) then the cache will not be used (as it looks like this class needs reweaving), but changing the set of aspects will not cause reweaving to happen (IIRC). So this is for a system that is pretty static in terms of aspects but you want faster startup on secondary starts. > Is there any Memory limit for Caching? ie. If only to certain extent > Caching is done or is unlimited?? disk space is the limiting factor I believe. > Is there any constraints(Where this feature is most applicable? ) to use > this feature? If you have a system where the set of aspects are fixed, this can work well for you. The bug report contains some performance metrics showing you the benefits. > It will be more helpful, if any use-cases provided or any documents > regarding this feature!! Unfortunately the only real docs are in the bugzilla, I haven't had the time to integrate anything into the main docs. There are further changes coming into this area on two fronts: - 'asynchronous' caching. It has become apparent that storing entries on the disk in the first start is a bottle-neck and slowing down that initial start. aynchronous caching will do the storing in a thread. - assume common aspects across all classloaders to give a further boost. If your system meets this requirement then the cache will actually be consulted during the initial start if it sees two classloaders loading the same class (only one will suffer the weaving cost). This can make the initial start faster than without caching (as well as speeding up the latter restarts). Andy _______________________________________________ aspectj-users mailing list aspectj-users@eclipse.org https://dev.eclipse.org/mailman/listinfo/aspectj-users
