[Interest] How to inspect a Qt Application memory usage?

[Elvis Stansvik]

Den mån 22 okt. 2018 kl 18:04 skrev Nuno Santos <nunosantos at imaginando.pt>:
>
> Elvis,
>
> I have just tried that it resulted in this. I’m not familiar with valgrind output. Does this look good to you?
>
>
> --45024-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option
> --45024-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 2 times)
> --45024-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 4 times)
> --45024-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 8 times)
> QML debugging is enabled. Only use this in a safe environment.
> ==45024==
> ==45024== Process terminating with default action of signal 11 (SIGSEGV)
> ==45024==  Access not within mapped region at address 0x18
> ==45024==    at 0x1077D6E3A: _pthread_wqthread (in /usr/lib/system/libsystem_pthread.dylib)
> ==45024==    by 0x1077D6BE8: start_wqthread (in /usr/lib/system/libsystem_pthread.dylib)
> ==45024==  If you believe this happened as a result of a stack
> ==45024==  overflow in your program's main thread (unlikely but
> ==45024==  possible), you can try to increase the size of the
> ==45024==  main thread stack using the --main-stacksize= flag.
> ==45024==  The main thread stack size used in this run was 8388608.
> --45024:0:schedule VG_(sema_down): read returned -4
> ==45024==
> [1]    45024 segmentation fault  valgrind --tool=massif XPTO.app

Hm, I'm not too familiar with valgrind output, but that looks like the
application crashed due to an access violation. Perhaps you should run
it in a memory error checker first to make pinpoint the violation?
Valgrind has one called memcheck (--tool=memcheck).

Elvis

>
> Thx!
>
> Nuno
>
> On 22 Oct 2018, at 16:54, Elvis Stansvik <elvstone at gmail.com> wrote:
>
> I used valgrind with valgrind --tool=massif myApp to track down a memory issue just today actually, and it worked out great, but I don't know if it works on macOS (this was on Linux). I used massif-visualizer for visualization.
>
> I've been meaning to check out heaptrack but haven't gotten around to it.
>
> Elvis
>
> Den mån 22 okt. 2018 16:50Nuno Santos <nunosantos at imaginando.pt> skrev:
>>
>> Hi,
>>
>> What tool(s) do you people suggest in order to investigate where is the memory being spent on a Qt application?
>>
>> Thanks!
>>
>> Nuno
>> _______________________________________________
>> Interest mailing list
>> Interest at qt-project.org
>> http://lists.qt-project.org/mailman/listinfo/interest
>
>