MonoTouch Running differently on IOS Emulator than on IPad - c#-4.0

I'm having issues around my app (basically a modified Mobile World Conference) app when I run it on the IOS Emulator in windows, verses running it directly on the IPad itself. I understand that there is a different process or involved so I don't expect it to be exactly the same.
In specific, I'm getting errors around initializing sql databases (SqlLite) with errors being
"Object Not Defined"
When I try and single step debug to the device, I get errors that feel like somehow the stack has been corrupted and I can not even debug into methods.
My question is, what are the types of differences I can look for and how to debug them? There must be some pattern of things that cause issues, I just have no idea what that is or how to figure it out. I'm use to my c# code just working on x86.

What causes simulator to behave differently? Simulator is not constrained in memory usage like a real device so you're likely to hit memory warnings on the device (and crash if you don't handle them properly). The code itself, however, runs faster so race conditions between threads are more likely, so watch out for that. Don't talk to database from different threads, or at least use proper locking. And of course there are AOT limitations which occur only on the device. Your LINQ problem sounds like a AOT problem to me.

Related

How would I detect infinite loops in Node.js?

I have a NodeJS app that seems to have an infinite loop due to persistent 100% CPU usage - https://github.com/3PG/Bot.
IDE: VSCode
I have changed many files and lines of code since June, but the problem still persists. I believe it is caused by an infinite loop.
How would I detect infinite loops in Node.js for TypeScript project?
I tried setting up your bot to try and replicate the situation. I disabled the API Module, XP Module, Bot Stats module and Music Module so that I could easily set it up without having to do much configuration. As you can see here, I can't replicate your situation as the Bot is running and it's using 0% of the CPU. It may have to do with the specs of your PC, but I can't replicate, so what I suggest to do is try and disabling various modules, so that you can find the one that's causing the CPU to burst.
I hope I helped you ;)

System.OutOfMemoryException error

We are working on a rich client application in which many threads are running as well third party controls are used, after running application for 1 hour it starts giving error of 'System.OutOfMemoryException' unless and until we restart the application, i have search many sites for help but no particular and specified reason is giving.
Thanks.
It sounds pretty self-explanatory, you're system doesn't have enough memory. If you're still running the application as 32-bit then moving to 64-bit might solve the problem. I had exactly that problem on a server-2008-r2 recently, and moving to 64 bit did solve my problem. But if you're already 64 bit then perhaps the server doesn't have enough physical memory. In which case, you need to add more memory, or work out how to make your application less memory hungry. There could be objects that could be discarded that it's keeping references to, etc, and if that's the case you should try profiling to try and identify what's hogging the most memory. Beyond that, does the application use any unmanaged DLLs, e.g. COM objects written in C++ or similar. Maybe there's a memory leak outside of the managed framework?
I recommend using a profiler to identify and find where does the high memory consumption come from.

Is it possible to force termination of backgrounding apps on iOS?

I've written an app which is handling videos. As we know, video processing takes a huge amount of memory while dealing with HD resolution. My App always seemed to crash. But actually I am 100% sure, that there is no memory leak in my code. Instruments is showing no leak.
At the beginning I am startin up one OpenGLES view and the video engine. For a very short time the memory consumption is high, but falling down to normal level after the initializations are done. I am always getting memory warnings during this period. Normally this is no problem. But if I have a lot of apps in suspended mode running, the App seems to be crashing. Watching into the crash log and using the debugger shows up, that I am only running out of memory.
My customers are flooding my support mail with "app is crashing" mails. But I do know, that they have too much Apps running in the background, so there is no memory left to go. I think it's bad style programing saying the customer that he has to close Background tasks before running the app.
According to this post this is a common problem.
My question is: Is it possible to tell the OS that one needs a lot of memory so the OS should terminate some suspended Apps? This memory stuff makes me crazy, because it's no bug I could fix.
No. It is not possible to affect anything outside of your sandbox without API calls. None exist for affecting other processes in the public API.
Have you tried to minimize your memory usage? In my experience once a memory warning it thrown apps can be more likely to have problems once they are in the background, even when memory usages drops.
If you are using OpenGLES and textures, if you haven't already compress your textures. What is the specific cause of your memory allocation spike?

J2ME: How to inspect application's crash which doesn't throw any visible exception?

I develop multimedial application within the Java ME platform. It's application usable for voice recording and after replaying.
I have treated many pieces of code by try/catch block, which should provide an alert in the case an exception occured. The application works fine on java emulator but on Symbian phone it seems fine but the application crashes after some minutes of working without any message and also without any system message. It just falls down, the application is abruptly terminated.
Is there any way how to find where's the problem? I've tried to surround all big pieces of code by try/catch block but the result is same.
Thanks for you advice
I recommend using the Symbian on device debugger or tracing on the device to determine the exact location of the problem.
You can log to file on the device every step that you make before it stops and after like "I'm doing XYZ" with timestamps and other stuff like variables values then try to figure out what is going on. Of course You'll get only stuff that happened before crash but it can give You some new info.

How to simulate a Windows Azure VM crash in my DevAppFabric

We need to think big and our applications need to scale in order to work on the Windows Azure Platform. But how do I simulate a crash of one of the VMs running my application?
I want to see (debug) how my application behaves in such environment.
Simulating faults is simple (just call Thread.Abord()); but it won't tell you much about your design.
In particular, debugging is a bit irrelevant, because whenever VM stop working there is nothing more to observe (nothing more to debug too). You should just assume that your app is likely to be abruptly stopped at any point of its execution.
Since, you cannot realistically observe all the subtle data corruptions that could be caused by interrupted executions, you should think to your persistence design to be resilient to such problem from the start (idempotent processes help a lot when possible).

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