I'm trying everything i can to get instruments to profile my app on the actual iphone device, but it won't work no matter what i do. I tried the solution from Does Instruments (ObjectAlloc/Leaks) require the simulator? but that didn't work. Most of the time i get nothing of use from the console, but one time i did receive this error:
Mon Aug 31 11:27:48 unknown
lockdownd[14] : (0x83d400)
handle_connection: Could not receive
USB message #13 from Instruments.
Killing connection
I'm not sure what could be causing this; has anyone else seen this and know a solution?
Same problem - it worked the first two times, then after that never again (even after restarting Xcode, deleiting the device, etc).
Eventually I resorted to:
Set XCode to display the Console
Run with Performance Tool
(instruments starts, and goes "BEEP"
with no error - Apple "forgot" to
include the error message, I think.
ARGH!)
Build&Run on device
Once the (gdb) appears in console,
go to Instruments and select "Attach
to Process" from the drop-down at
top
If you cannot see the name of your
debugging app, wait a second, and
try again
Eventually your app appears in the
list of alread-running stuff, so
select it
Hit the Record button
On subsequent runs, Instruments will remember the name of your app, but will show an error if you hit "record" too soon. So you just keep hitting record and doing "OK" on the process it tries to connect to until it stops messing around and does what it's supposed to.
So far (20 odd runs) this works everytime. Obviously, it would be nicer if it just worked properly, without this manual hackery, but Apple is reporting zero error messages even to system console, so there's nothing we can do!
Related
Im facing an issue that i am unable to debug.
If i open the app, it opens normally and works. But if i launch the app and close the app within 1 second and then launch the app again, it crashes without error message.
How do i debug this as Xcode loses debug connection if i close the app?
I tried putting exception break point but since xcode loses debug connection, it wont trigger.
This ONLY happens when a user does the above mentioned steps (open, close within 2 seconds and open again).
Is there anyway to find out why the app is closing and why there is no error / crash message?
Clarification : The crash happens when user opens the app, within 1 sec terminates the app by manually by swiping up from recents menu and tries to open the app again within 1 or 2 seconds. (Open -> terminate -> open)
Let us imagine that you run the app and quickly force-quit. Then, if you start your second run of the app from the Xcode debugger, hopefully, you should see your crash in Xcode at that point.
If that does not work, you might consider a crash reporting tool (e.g., Crashlytics, etc.). That will help you monitor and track crash reports that happen (for both you and your users) in the wild. If you do this, make sure you test the crash reporting system with some forced crash/report because an absence of a report could just be a result of a misconfiguration, which is easy to do because the setup of these tools takes a little work the first time you do it. Just make sure you have the crash report system working with a positive crash report before you draw any conclusions from an absence of a crash report generated by this particular bug.
That having been said, the way these crash reporting systems often work is they capture the crash and send it the next time you start up the app. It seems like there might be a chance that your particular crash (firing it up after having quickly force-quit it the first time) is happening so fast that the crash reporting system may not have a chance to send off its report of the past crash. (That having been said, these are still invaluable for capturing information about user crashes that happen during the normal use of the app, so I would consider them even if it does not help in this particular scenario.)
So, let’s imagine that you are still unsuccessful in catching your crash for some reason. The last resort is to consider sprinkling your code with Logger/OSLog statements. The nice thing about these logging statements is that you can watch these logging statements on your macOS Console app. See WWDC 2020 Explore logging in Swift.
I have a question which seems like it should be a fairly common occurrence. I am trying to test code which only runs the first time an ios application is installed. While in principle this is very easy, I'm having trouble with it behaving properly the second time the app runs (note, this is not crash related).
I have been force running the app for a second time using the "Application does not run in background" flag in the plist, and then just hitting the home button. This works great, except i stop getting log data after the first run.
Does anyone know how to test for this situation in a way where you can continue seeing the log information after the app closes? For example, if there is a way to attach the xcode logger to the new process id? Or just another way to force an app reboot without losing the logging feature?
Thanks in advance!
Use the debugger menu:
Product>Attach To Process
(Results may vary with different versions of Xcode).
Also, you might need to insert a sleep at the very start of your launch to catch the very early log messages.
EDIT: If you're on a device then you can use the Device Organizer (cmd+shift+2) to watch all logs on a device.
I updating my database with a lightweight migration. If I do the update on my device through xcode in debug mode everything runs fine. If I load the app through iTunes as a archive file it will crash before loading the rootViewController. This only happens with my large test database >100mb. I don't get anything useful in the crash log and am not sure what to do with this.
His is the only relevant line I can find in the crash log.
Unknown thread crashed with unknown flavor: 5, state_count: 1
Normally this would be reflected in the crash report (It would say something about failing to launch in time) but iOS devices expect you to get a view on the screen (or for ApplicationDidFinishLaunching to finish, I'm not sure exactly what it looks for) in a certain amount of time or it just gives up and closes the app. If you are doing a significant amount of work you'll want to get some kind of screen up before you start that work. Unfortunately this doesn't happen in a debug environment so it's a pain to test.
so when i'm running my app using XCode and I can see that my app gets "program received signal 0".
However , the background thread are still running. why is that ?
Second, I can't seem to find any solution to this problem.
I assumed it might be memory leak, but I see nothing special using LEAKS (instrument).
When I run the app on the device(without XCode) and then try to see the device crash inside the organizer, most of the times there is no log (I guess maybe because the app is still running and only the main thread crashed) and while there is a log, my app function are only hex addresses without names.
What other options do I have to solve this issues ?
Thanks!!
I've found that sometimes these errors are caused by trying to access deallocated memory. One great tool to debug these issues is NSZombieEnabled. Here's a link to a good explanation of how to use NSZombieEnabled: CocoaDev: NSZombieEnabled
I have some users testing my app on Windows and Mac platforms. The app crashes at some points but the Windows users cannot get any crash logs. Here's what they do
Run the app and play around till it crashes
Sync their device with iTunes
Look for logs here (on a Vista) C:\Users\\AppData\Roaming\Apple computer\Logs\CrashReporter\MobileDevice\
But there is nothing inside the Apple Computer folder.
Any ideas? Thanks.
Aside from you omitting parts of the path in that it should correctly be containing the login username - ow, now noticed you possibly did try to embed it, hence the double backspace after Users....
Ask your user if he possibly is using multiple computers for syncing his device. In case he does, he should check the machine he used first as those Logs are only synced with the "main"-machine, I believe. Bit of a shot in the dark but worth the attempt, I think.
Ow, and there may be another possible reason I just saw within another thread - credits to Kendall:
If there is not crash log, it could mean the app was shut down for using too much memory - in that case you should see a message come up in the device console indicating your application is being shut down.