Performance issue in my WP7 game

Performance issues in my simple WP7 game.
Yes it is true, my simple game has juddering going on. Which i hate. This post is about the way it looks and the frustration of the problem.

To start with i will list what i am doing in the Update, then follow that with the small list of what is in the draw call.

Update:

• Base update
• Some sprite effects (about 10 or so usually) (i can run thousands with no discernable change in frame rate)
• The hotspot update code
• Game code which tests for win/lose conditions
• Cards control, moves the cards in their inertial direction (14 cards moving total !)

Draw:

• Base
• Background (fuill screen)
• 16 cards (2d sprites)
• my scales (3 x 2d sprites)
• Some text for score and pause etc

and that is it. Not a lot there eh? Yet  i experience some juddering, now my preliminary test (the only one i did while half asleep last night) was to comment out the Admanager update. With that removed my frame rate seemed very stable, but i was half asleep, so maybe it was only half stable haha.

With such a simple game it is quite frustrating to run into these issues. Now maybe i am running into garbage collection issues with the way i am doing something in this code. That is very possible and something i ran into several times on the Xbox development i have done. The effects manager i am using came from the Xbox dev after i optimized it to not produce garbage.

Tonight when i get back to this i will be performaing some more surgery by simply cutting parts out and see what happens. If i cannot trace the problem, then it will be time for some sort of profiling. Something i have no experience on for Xna (yeah, i never needed it for my Xbox shooters, even though Pellmell would gladly put on 10,000 effects etc). As for the extra juddering that happens when i do an Ad.Refresh call (to get a new Ad), i think i might have to come up with a better solution for that, though i have no idea what. The bright spark of hope lies in the fact that one of my mates @KrisWD40 (on twitter) has a great game out and he does not suffer this juddering with his ad manager refreshes (his game is Hypership out of control).

I will report back when i have some news on this, as i am sure other people will run into some similar issues.
Da Voodoochief