Flex Performance Tuning Tips
Wednesday, June 27th, 2007Flex Speed Tips: Matt chotin has shared a some great tips to improve Flex performance which I came through and would like to share with the community,
- If you have a type in AS3, which you are not sure of always use the As operator to cast the type before you use it. This avoids VM errors with try/catch, which slow the execution and is ten times slower than the As operator.
- Array is access is slow if the array is sparse. It may be faster to put nulls in empty values as this speeds things up. Array misses are very slow, up to 20 times slower than finding a valid entry.
- Avoid implicit type conversion. In the player it will convert integers to numbers and back when asked to add integers. You might as well use numbers for everything and convert back to integer at the end.
- Local variable access is faster, so assign variables to local if they are accessed a lot. They will be stored on the stack and access is much quicker.
- Data Binding expressions take up memory and can slow down the application startup. It may be more efficient to do an assignment in code rather than using binding.
- Find a slow computer and run your application. If it runs OK ship it! Other wise you can use flash.utils.getTimer():int to get a time value in miliseconds before and after some process to time it.
- In Flex Builder 3 there is a profiler that allows you to take performance snapshots to record how long was spent in each function. This is useful to identify the areas of code that might benefit from optimization. While profiler is running everything is much slower. Often Mouse or similar Events will seem to take lots of time, you can ignore these. Investigate your own functions and see if they have been called too often or they take too long.
and was much more exciting than expected. We had great Guru’s of Flex there passionate about talking Flex, promoting Flex and keeping their efforts to see a real Web 2.0 world.