Android Question Resumable Sub Execution Speed Vs. Regular Sub

[Jeffrey Cameron]

I'm coding a guessing-game project where I have a finite set of integer value possibilities to iterate through and I'm seeing something odd. I made a sub that goes through the integer item set (46,656 at most) eliminating non-matching items based on a comparator.

When the sub is just a tight loop that returns the result, it takes 4-7 seconds to execute (during which time the app is completely unresponsive, obviously). If I make an exact copy of the block that has a sleep(0) before the loop start and raise an event afterwards via callsubdelayed (no sleep inside the loop at all) it takes upwards of six minutes and change to execute:

'  App started
clsAI.LoadPatterns: Combintaions(46656) vs. Map(46656).
PROCESS COMPLETE: NewGame
'  --- Tight loop first ----
Guess #1 took 0:04. Result: 0 exact & 3 matches.
Eliminated 44404 possibilities, 2252 remaining.
'  Took four seconds and change

' --- app stopped and restarted, then resumable sub loop used

Guess #1 took 6:58. Result: 1 exact & 2 matches.
Eliminated 39818 possibilities, 6838 remaining.
'  Took nearly seven minutes!

I cut-and-pasted the code block so I know the only difference between the two procedures is the Sleep(0) before the loop and the CallSubDelayed after the loop completes instead of Return Result. Originally I had the sleep inside the loop with an "index mod 500 = 0" throttle on it, and experienced this behavior so I took that out completely and put a sleep before the loop just make sure the sub was resumable.

Why would this change produce such a vast performance difference? And, if this is behavior as intended, would the deprecated "DoEvents" in the first method allow the UI to be responsive without the performance hit?

 

[stevel05]

Without seeing the code, it's impossible to test or guess, but did you run the tests in release mode?

 

[Jeffrey Cameron]

Good catch on the release mode, since I'm using an actual Galaxy S5 for testing I didn't think to try debug vs. release.

In debug mode I see the massive delay between the procedures, in release mode, both procedures produce the same result. I guess I'll just leave it in release mode while I develop .

Thank you, @stevel05!

 

[Erel]

This is a debug-only issue. It is related to an important optimization that is currently not applied to resumable subs.

In some cases you can move the "heavy code" to a different sub and call it from the resumable sub. This way it will run fast in debug mode. Make sure to clean the project before you test it.