Today I investigated the performance-effects of dynamic imports. Replacing the dynamic imports with static imports reduces the start time of my system by about ~10%. (it depends on how many imports you have)
My summary... If someone asks me how to reduce the startup time, then I would suggest him: 1. *Reduce / avoid (transitive) dependencies at all.* (Choose thirdparty bundles with less transitive dependencies.) I achieved the biggest speed boost by far by downgrading of Log4j2 to Log4j1.2. 2. Embed all transitive dependencies together with the library you want to wrap. 3. Embed thirdparty bundles like log4j & Co. in the systembundle and export them with FRAMEWORK_SYSTEMPACKAGES_EXTRA. 4. Extract all classes of an embedded library into your wrapper bundle. (inline=true) 5. Avoid dynamic imports. 6. Declare unnecessary / "unused" package dependencies as optional. (resolution:=optional). 7. Use lazy activation. 8. Use hooks / threads in the BundleActivator-callbacks if you have to wait / synchronize. 9. Do not implement Declarative Services if you have to synchronize threads. (You have to wait until all DS are registered, but that can happen very late.) 10. Do not use the LogService, implement your own org.apache.felix.framework.Logger instead. 11. Do not clean the bundle cache before startup, *start only cached bundles*! Did I forget something? best regards Roland -- View this message in context: http://apache-felix.18485.x6.nabble.com/How-to-improve-the-start-time-of-Apache-Felix-tp5004833p5005101.html Sent from the Apache Felix - Users mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
