iOS memory and performance challenges

[Charlie Hitchcock]

I'm curious if anyone has any suggestions for how to best resolve two iOS problems we are facing:

1. a slow memory loss that is not being picked up in Instruments / Leaks. We've done some work with heapshots, but just not clear to us how to track this down.

2. poor performance during loading of some view controllers, especially bad on slow 4th gen iPod touches.

Any thoughts, ideas, or references are welcome. Thanks.

[Mike Morton]

1. a slow memory loss that is not being picked up in Instruments / Leaks. We've done some work with heapshots, but just not clear to us how to track this down.

What evidence leads you to think there is a memory leak, since Instruments doesn’t see it?

2. poor performance during loading of some view controllers, especially bad on slow 4th gen iPod touches.

Does Instruments give any hints?

Plain old printf (I am here and the time is…) can show you some things, but not as useful if you’re multithreaded.

-- Mike

[Jim Matthews]

When we were having slow memory loss problems with Roadshow (2011) we wrote UIAutomation scripts to drive the problem. I don't think they directly uncovered the sources of the problem, but they did give us a metric for judging whether we were making progress (the script tried to open 100 web pages, and originally we'd run out of memory after 30 or so; eventually we could do the whole list).

What I really wanted was a way to run the UIAutomation script at the same time as the leaks and/or heapshot instruments, so we could see where the memory was going. Every time I tried Instruments crashed. I complained about it at WWDC, and they said it should work now, but I haven't gone back to check.
--
Jim Matthews
Fetch Softworks
http://fetchsoftworks.com