There are currently a few different ways at getting timing information from Xamarin.Android & Mono. This document aims to demystify the command-line commands involved in retrieving this data from Android devices.
This document explains many uses of adb at the command-line. On
Windows, you will need either adb.exe in your %PATH% or a
powershell alias for adb.
The easiest way to time the complete time of startup is to launch the app by tapping the icon, and run:
# Windows / Powershell
> adb logcat -d | Select-String Displayed
# Mac / Unix
> adb logcat -d | grep Displayed
NOTE: going forward, I will just use grep in examples. On Windows, keep in mind to use Select-String if needed.
Both platforms will output something such as:
09-04 14:33:32.466 1169 1192 I ActivityManager: Displayed com.xamarin.android.helloworld/example.MainActivity: +1s3ms
The ActivityManager system process logs how long it takes for any
Android activity to start. This is the best measure of overall time
taken: reflecting what a user experiences when launching the app.
You can also run adb logcat -c to clear the log at any point.
Before launching the app, run the adb command:
> adb shell setprop debug.mono.log timing=bare
After launching the app, we get additional information:
> adb logcat -d | grep monodroid-timing
09-04 14:44:11.968 9126 9126 I monodroid-timing: Runtime.init: Mono runtime init; elapsed: 0s:0::620209
09-04 14:44:11.995 9126 9126 I monodroid-timing: Assembly load: HelloLibrary.dll preloaded; elapsed: 0s:1::92917
09-04 14:44:11.995 9126 9126 I monodroid-timing: Finished loading assemblies: preloaded 2 assemblies; wasted time: 0s:1::111927
09-04 14:44:12.026 9126 9126 I monodroid-timing: JNIEnv.Initialize start
09-04 14:44:12.043 9126 9126 I monodroid-timing: JNIEnv.Initialize: Logger JIT/etc. time: elapsed 14 ms]
09-04 14:44:12.192 9126 9126 I monodroid-timing: JNIEnv.Initialize: managed runtime init time: elapsed 148 ms]
09-04 14:44:12.238 9126 9126 I monodroid-timing: TypeManager.cctor start: 1567626252195.41
09-04 14:44:12.255 9126 9126 I monodroid-timing: TypeManager.cctor time: 1567626252254.66 [elapsed: 59.248 ms]
09-04 14:44:12.255 9126 9126 I monodroid-timing: JNIEnv.Initialize: TypeManager init time: elapsed 63 ms]
09-04 14:44:12.363 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives ("Android.Runtime.UncaughtExceptionHandler, Mono.Android", 0x7fd311c2cc) start: 1567626252360.4
09-04 14:44:12.420 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives total time: 1567626252420.89 [elapsed: 60.492 ms]
09-04 14:44:12.421 9126 9126 I monodroid-timing: Runtime.register: end time; elapsed: 0s:62::781621
09-04 14:44:12.437 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives ("Java.Interop.TypeManager+JavaTypeManager, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", 0x7fd311b9ec) start: 1567626252437.71
09-04 14:44:12.439 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives total time: 1567626252439.4 [elapsed: 1.684 ms]
09-04 14:44:12.439 9126 9126 I monodroid-timing: Runtime.register: end time; elapsed: 0s:1::757865
09-04 14:44:12.446 9126 9126 I monodroid-timing: JNIEnv.Initialize end: elapsed 479 ms
09-04 14:44:12.446 9126 9126 I monodroid-timing: Runtime.init: end native-to-managed transition; elapsed: 0s:443::816399
09-04 14:44:12.446 9126 9126 I monodroid-timing: Runtime.init: end, total time; elapsed: 0s:480::702704
09-04 14:44:12.459 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives ("HelloWorld.MainActivity, HelloWorld", 0x7fd311ceec) start: 1567626252459.23
09-04 14:44:12.470 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives total time: 1567626252470.37 [elapsed: 11.144 ms]
09-04 14:44:12.470 9126 9126 I monodroid-timing: Runtime.register: end time; elapsed: 0s:11::259949
09-04 14:44:12.559 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives ("Android.Views.View+IOnClickListenerImplementor, Mono.Android", 0x7fd311b5fc) start: 1567626252559.64
09-04 14:44:12.561 9126 9126 I monodroid-timing: JNIEnv.RegisterJniNatives total time: 1567626252561.82 [elapsed: 2.182 ms]
09-04 14:44:12.561 9126 9126 I monodroid-timing: Runtime.register: end time; elapsed: 0s:2::244636
These are timings taken at different points during Xamarin.Android startup: across native and managed code.
In case you have the XA build tree by hand, it is possible to process that information like:
> msbuild /v:d build-tools/timing/timing.csproj /t:LogcatTiming /p:PID=3011 # process id of your application
...
Task "ProcessLogcatTiming"
Time: 0ms process start, application: '' PID: 3011
Time: 57ms Message: Runtime.init: Mono runtime init; elapsed: 0s:0::44834
Time: 65ms Message: Finished loading assemblies: preloaded 1 assemblies; wasted time: 0s:0::49
Time: 73ms Message: JNIEnv.Initialize start
Time: 78ms Message: JNIEnv.Initialize: Logger JIT/etc. time: elapsed 3 ms]
Time: 101ms Message: JNIEnv.Initialize: managed runtime init time: elapsed 22 ms]
Time: 113ms Message: TypeManager.cctor start: 1567669218343.18
Time: 116ms Message: TypeManager.cctor time: 1567669218357.74 [elapsed: 14.563 ms]
Time: 117ms Message: JNIEnv.Initialize: TypeManager init time: elapsed 15 ms]
Time: 156ms Message: JNIEnv.RegisterJniNatives ("Android.Runtime.UncaughtExceptionHandler, Mono.Android", 0xffe3c454) start: 1567669218396.28
Time: 163ms Message: JNIEnv.RegisterJniNatives total time: 1567669218404.38 [elapsed: 8.097 ms]
Time: 163ms Message: Runtime.register: end time; elapsed: 0s:8::800097
Time: 164ms Message: JNIEnv.RegisterJniNatives ("Java.Interop.TypeManager+JavaTypeManager, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", 0xffe3bcf4) start: 1567669218405.08
Time: 164ms Message: JNIEnv.RegisterJniNatives total time: 1567669218405.86 [elapsed: 0.787 ms]
Time: 164ms Message: Runtime.register: end time; elapsed: 0s:0::813062
Time: 166ms Message: JNIEnv.Initialize end: elapsed 105 ms
Time: 166ms Message: JNIEnv.Initialize end: elapsed 105 ms
Time: 166ms Message: Runtime.init: end native-to-managed transition; elapsed: 0s:100::17520
Time: 166ms Message: Runtime.init: end native-to-managed transition; elapsed: 0s:100::17520
Time: 166ms Message: Runtime.init: end, total time; elapsed: 0s:109::900001
Time: 173ms Message: JNIEnv.RegisterJniNatives ("xatemplateaot.MainActivity, xatemplateaot", 0xffe3cbe4) start: 1567669218414.33
Time: 173ms Message: JNIEnv.RegisterJniNatives total time: 1567669218414.89 [elapsed: 0.552 ms]
Time: 173ms Message: Runtime.register: end time; elapsed: 0s:0::594434
Time: 232ms Message: JNIEnv.RegisterJniNatives ("Android.Views.View+IOnClickListenerImplementor, Mono.Android", 0xffe3bb54) start: 1567669218473.37
Time: 232ms Message: JNIEnv.RegisterJniNatives total time: 1567669218473.59 [elapsed: 0.219 ms]
Time: 232ms Message: Runtime.register: end time; elapsed: 0s:0::241370
-- Performance summary --
Last timing message: 232ms
Done executing task "ProcessLogcatTiming".
...
An example of these log messages would be this managed call or this native call.
The application needs to be built with embedded AOT profiler, the
profiler needs to be enabled and the application run on device or
emulator. That can be done by using BuildAndStartAotProfiling
target:
> msbuild /t:BuildAndStartAotProfiling <your.csproj>
Related to that target is $(AndroidAotProfilerPort) property, which can
be used to choose the socket port number for communication with the
profiler. The default value is 9999.
Once the application starts, the FinishAotProfiling target can be
used to collect the profile from the device or emulator:
> msbuild /t:FinishAotProfiling <your.csproj>
The FinishAotProfiling target uses the $(AndroidAotProfilerPort) for
socket port number and $(AndroidAotCustomProfilePath) for the newly
created profile file, the default value is custom.aprof.
The profile can be used to build your app with AOT profile. Add it to
the @(AndroidAotProfile) item group in your .csproj file and set the
$(AndroidEnableProfiledAot) property to true. You might also disable
the default AOT profile with $(AndroidUseDefaultAotProfile)
property. Part of your .csproj file might look like:
<ItemGroup>
<AndroidAotProfile Include="$(MSBuildThisFileDirectory)custom.aprof" />
</ItemGroup>
<PropertyGroup>
<AndroidEnableProfiledAot>true</AndroidEnableProfiledAot>
<AndroidUseDefaultAotProfile>false</AndroidUseDefaultAotProfile>
</PropertyGroup>The profile itself can be inspected and optionally filtered by the
aprofutil tool.
Using the AOT profile is useful for scenarios like speeding up the startup of your application or other performance critical parts, by selectively AOT'ing only the methods included in the profile.
Before launching the app, run the adb command:
> adb shell setprop debug.mono.log timing,default
After launching the app, you can find a file that was recorded during startup:
> adb shell run-as com.xamarin.android.helloworld ls files/.__override__
counters.txt
methods.txt
Make sure to use your app's package name instead of
com.xamarin.android.helloworld.
You can pull these files to your machine by doing:
> adb shell run-as com.xamarin.android.helloworld cat files/.__override__/counters.txt > counters.txt
> adb shell run-as com.xamarin.android.helloworld cat files/.__override__/methods.txt > methods.txt
If you ever need to reset/clear these directories, you can uninstall/reinstall the app or merely:
> adb shell run-as com.xamarin.android.helloworld rm -r files/.__override__/
counters.txt has some interesting summary information provided by
Mono:
## Runtime.register: type=HelloWorld.MainActivity, HelloWorld
JIT statistics
Discarded method code : 1
Time spent JITting discarded code : 0.82 ms
Try holes memory size : 896
Dynamic code allocs : 3
Dynamic code bytes : 584
Dynamic code frees : 0
Unwind info size : 5985
Calls to trampolines : 1994
JIT trampolines : 952
Unbox trampolines : 2
Static rgctx trampolines : 7
Async JIT info size : 0
Max native code in a domain : 0
Max code space allocated in a domain: 0
Total code space allocated : 0
Hazardous pointers : 0
Compiled methods : 921
Methods from AOT : 0
Methods JITted using mono JIT : 921
Methods JITted using LLVM : 0
Methods using the interpreter : 0
methods.txt has the individual JIT times of each method:
JIT method begin: System.OutOfMemoryException:.ctor (string) elapsed: 0s:20::136721
JIT method done: System.OutOfMemoryException:.ctor (string) elapsed: 0s:20::605627
This is not particularly readable, so you can use our jit-times command-line tool to get better/sorted output:
# Windows / .NET
jit-times.exe methods.txt > methods-sorted.txt
# Mac / Mono
mono jit-times.exe methods.txt > methods-sorted.txt
Which outputs:
| Total (ms) | Self (ms) | Method |
|---|---|---|
| 20.08 | 20.08 | System.Reflection.Emit.OpCodes:.cctor () |
| 23.29 | 19.61 | Java.Interop.JniRuntime:.ctor (Java.Interop.JniRuntime/CreationOptions) |
| 9.34 | 8.59 | Android.Runtime.JNIEnv:Initialize (Android.Runtime.JnienvInitializeArgs*) |
| 5.74 | 5.74 | string:SplitInternal (string,string[],int,System.StringSplitOptions) |
| 5.17 | 5.17 | System.Text.StringBuilder:AppendFormatHelper (System.IFormatProvider,string,System.ParamsArray) |
| 4.74 | 4.74 | Java.Interop.JniRuntime:InitJniBuiltinTypeNameMappings () |
| 4.60 | 4.60 | Java.Interop.JniRuntime:InitJniBuiltinArrayMappings () |
| 4.41 | 4.41 | Java.Interop.JniRuntime/JniTypeManager/d__11:MoveNext () |
| 4.25 | 4.07 | System.MonoCustomAttrs:GetCustomAttributes (System.Reflection.ICustomAttributeProvider,System.Type,bool) |
| 24.31 | 3.92 | Android.Runtime.JNINativeWrapper:CreateDelegate (System.Delegate) |
| 19.64 | 3.79 | Java.Lang.Thread:get_DefaultUncaughtExceptionHandler () |
For further details see jit-times' README.md.
Before launching the app, you can enable Mono profiling via:
> adb shell setprop debug.mono.profile log:calls
Anything after debug.mono.profile is the --profile switch
described on the Mono documentation.
Now when launching the app, you get a new file:
> adb shell run-as com.xamarin.android.helloworld ls files/.__override__
profile.mlpd
This profile.mlpd file is a binary file, so we can't just pipe it to
a file with >. I used a known writeable directory on my device such
as /sdcard/Download/:
> adb shell run-as com.xamarin.android.helloworld cp files/.__override__/profile.mlpd /sdcard/Download/
> adb pull /sdcard/Download/profile.mlpd
/sdcard/Download/profile.mlpd: 1 file pulled. 24.8 MB/s (823327 bytes in 0.032s)
To view this file in a readable format, you can use mprof-report:
$ mprof-report profile.mlpd > profile.txt
NOTE: on Windows, I used mprof-report from WSL/bash, since it appears to not be distributed in the Mono Windows installer.
Your output will be something like:
Mono log profiler data
Profiler version: 3.0
Data version: 17
Arguments: log:calls,output=/data/user/0/com.xamarin.android.helloworld/files/.__override__/profile.mlpd
Architecture: armv8
Operating system: linux
Mean timer overhead: 47 nanoseconds
Program startup: Wed Sep 4 10:46:50 2019
Program ID: 11929
Server listening on: 44657
JIT summary
Compiled methods: 1454
Generated code size: 459916
JIT helpers: 0
JIT helpers code size: 0
GC summary
GC resizes: 0
Max heap size: 0
Object moves: 0
Method call summary
Total(ms) Self(ms) Calls Method name
465 0 1 (wrapper runtime-invoke) <Module>:runtime_invoke_void_JnienvInitializeArgs* (object,intptr,intptr,intptr)
465 9 1 Android.Runtime.JNIEnv:Initialize (Android.Runtime.JnienvInitializeArgs*)
171 0 3 (wrapper native-to-managed) Android.Runtime.DynamicMethodNameCounter:3 (intptr,intptr,intptr)
171 0 3 (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter:3 (intptr,intptr,intptr)
170 2 3 Android.App.Activity:n_OnCreate_Landroid_os_Bundle_ (intptr,intptr,intptr)
162 6 1 Android.Runtime.AndroidRuntime:.ctor (intptr,intptr,bool,intptr,intptr)
153 2 3 HelloWorld.MainActivity:OnCreate (Android.OS.Bundle)
147 0 21 (wrapper runtime-invoke) object:runtime_invoke_void (object,intptr,intptr,intptr)
132 1 14 Java.Interop.JniPeerMembers:.ctor (string,System.Type)
124 0 8 (wrapper runtime-invoke) object:runtime_invoke_void (object,intptr,intptr,intptr)
117 7 1 Java.Interop.JniRuntime:.ctor (Java.Interop.JniRuntime/CreationOptions)
106 6 14 Java.Interop.JniPeerMembers:.ctor (string,System.Type,bool,bool)
105 0 57 Java.Interop.JniRuntime/JniTypeManager:GetTypeSignature (System.Type)
100 0 4 (wrapper runtime-invoke) <Module>:runtime_invoke_void_intptr_int_intptr_intptr_int (object,intptr,intptr,intptr)
100 2 4 Android.Runtime.JNIEnv:RegisterJniNatives (intptr,int,intptr,intptr,int)
99 1 57 System.Linq.Enumerable:FirstOrDefault<Java.Interop.JniTypeSignature> (System.Collections.Generic.IEnumerable`1<Java.Interop.JniTypeSignature>)
99 0 10 Java.Interop.JniEnvironment/InstanceMethods:CallNonvirtualVoidMethod (Java.Interop.JniObjectReference,Java.Interop.JniObjectReference,Java.Interop.JniMethodInfo,Java.Interop.JniArgumentValue*)
98 5 57 System.Linq.Enumerable:TryGetFirst<Java.Interop.JniTypeSignature> (System.Collections.Generic.IEnumerable`1<Java.Interop.JniTypeSignature>,bool&)
Note: the times in the method call summary above include the time to JIT the method. The JIT time can be significant, for methods which are called just once it can be 50% of that time for example.
simpleperf is a tool included with the Android NDK for profiling native code.
If using the Visual Studio installation, you find this tool in
C:\Program Files (x86)\Android\android-sdk\ndk-bundle\simpleperf.
It also requires an installation of python.
Step 1, you will need to setup a shell script inside your app. You will take these files:
C:\Program Files (x86)\Android\android-sdk\ndk-bundle\wrap.sh\asan.arm64-v8a.shC:\Program Files (x86)\Android\android-sdk\ndk-bundle\wrap.sh\asan.armeabi-v7a.shC:\Program Files (x86)\Android\android-sdk\ndk-bundle\wrap.sh\asan.x86.shC:\Program Files (x86)\Android\android-sdk\ndk-bundle\wrap.sh\asan.x86_64.sh
You will need to place these files inside your app as AndroidAsset,
renamed to these paths:
Assets\lib\arm64-v8a\wrap.shAssets\lib\armeabi-v7a\wrap.shAssets\lib\x86\wrap.shAssets\lib\x86_64\wrap.sh
If you plan on profiling on a single device, I would only do this for the single ABI you need.
To profile app startup, I was running the command:
python app_profiler.py -p com.yourcompany.yourapp -a yourpackage.MainActivity
app_profiler.pyis"C:\Program Files (x86)\Android\android-sdk\ndk-bundle\simpleperf\app_profiler.py"- You might additionally need
--ndk_path="C:\Program Files (x86)\Android\android-sdk\ndk-bundle\simpleperf"
This generates a bunch of files in the current directory, such as:
binary_cache\, perf.data, and perf.report.
To view the results, run commands such as:
> python report.py
Cmdline: /data/data/Xamarin.Forms_Performance_Integration/simpleperf record --in-app --tracepoint-events /data/local/tmp/tracepoint_events -o perf.data -e task-clock:u -f 1000 -g --duration 10 --symfs /data/local/tmp/native_libs/ --app Xamarin.Forms_Performance_Integration
Arch: x86
Event: task-clock:u (type 1, config 1)
Samples: 1558
Event count: 1558000000
Overhead Command Pid Tid Shared Object Symbol
97.88% Xamarin.Forms_Performance_Integration 6527 6527 [vdso] __vdso_clock_gettime
0.13% RenderThread 6527 6548 [vdso] __vdso_clock_gettime
0.13% Xamarin.Forms_Performance_Integration 6527 6527 /system/lib/libdexfile.so art::IsValidPartOfMemberNameUtf8(char const**)
0.06% Binder:6527_3 6527 6542 [vdso] __vdso_clock_gettime
0.06% Jit thread pool 6527 6533 [vdso] __vdso_clock_gettime
0.06% Xamarin.Forms_Performance_Integration 6527 6527 /data/app/Mono.Android.DebugRuntime-wbwmv22rlkqD4wNWY5gjpQ==/lib/x86/libmonosgen-32bit-2.0.so libmonosgen-32bit-2.0.so[+21bf4c]
0.06% Xamarin.Forms_Performance_Integration 6527 6527 /data/app/Mono.Android.DebugRuntime-wbwmv22rlkqD4wNWY5gjpQ==/lib/x86/libmonosgen-32bit-2.0.so libmonosgen-32bit-2.0.so[+23ddf9]
...
Or some other examples:
> python report.py --sort dso
Cmdline: /data/data/Xamarin.Forms_Performance_Integration/simpleperf record --in-app --tracepoint-events /data/local/tmp/tracepoint_events -o perf.data -e task-clock:u -f 1000 -g --duration 10 --symfs /data/local/tmp/native_libs/ --app Xamarin.Forms_Performance_Integration
Arch: x86
Event: task-clock:u (type 1, config 1)
Samples: 1558
Event count: 1558000000
Overhead Shared Object
98.14% [vdso]
0.71% /system/lib/libart.so
0.58% /data/app/Mono.Android.DebugRuntime-wbwmv22rlkqD4wNWY5gjpQ==/lib/x86/libmonosgen-32bit-2.0.so
0.32% /system/lib/libdexfile.so
0.19% /system/lib/libc.so
0.06% /system/lib/libandroidfw.so
Or to get a full tree with a GUI:
> python report.py -g --gui
See further details on simpleperf's README.
At a high level, you can get a performance summary from MSBuild via:
> msbuild YourProject.csproj /clp:performancesummary
This prints out a breakdown for evaluation, and every MSBuild task & target:
Project Evaluation Performance Summary:
12 ms samples\HelloWorld\HelloLibrary\HelloLibrary.csproj 1 calls
98 ms samples\HelloWorld\HelloWorld.csproj 1 calls
Target Performance Summary:
275 ms _UpdateAndroidResgen 2 calls
354 ms _GenerateJavaStubs 1 calls
665 ms _CompileJava 1 calls
684 ms CoreCompile 2 calls
865 ms _ResolveSdks 2 calls
953 ms ResolveProjectReferences 2 calls
1219 ms _CompileToDalvikWithD8 1 calls
Task Performance Summary:
681 ms Csc 2 calls
809 ms ValidateJavaVersion 2 calls
983 ms MSBuild 5 calls
1217 ms D8 1 calls
Depending on what you're looking for, the MSBuild target timings may
be the most useful. <MSBuild/> or <CallTarget/> task calls can be
misleading, because they merely invoke other targets and don't spend
much time themselves.
See the MSBuild documentation for details about
/clp:performancesummary.
Using MSBuild binary logs is helpful for performance profiling, as well as general MSBuild "debugging". You can generate a binary log with:
> msbuild YourProject.csproj /bl
This will generate a msbuild.binlog file in the current directory
you can open with the MSBuild Binary Log Viewer.
In addition to showing you absolutely everything about the build, it can show the top 10 most expensive tasks:
Top 10 most expensive tasks
D8 = 3.895 s
AndroidApkSigner = 2.555 s
BuildApk = 2.396 s
Javac = 2.060 s
ResolveLibraryProjectImports = 1.246 s
LinkAssembliesNoShrink = 840 ms
CallTarget = 814 ms
Aapt2Link = 812 ms
Exec = 657 ms
Aapt2Compile = 623 ms
It also has a timeline view:
For Visual Studio on Windows, you can use the Project System
Tools extension for recording .binlog files.
This is extremely useful, as you can get logs for IDE-specific builds,
such as design-time builds or builds related to the Android designer.
In Visual Studio for Mac, the only option for measuring build times at
the moment is to enable diagnostic build logging.
Diagnostic logging includes the results of /clp:performancesummary
in the build output window.
Important! Using diagnostic MSBuild logging slows down the build quite a bit! Even a "short" build with no changes can take as much as 3X longer! Keep that in mind while profiling.
Similiar to how you can use the Mono Profiler
on Android, you can also profile MSBuild with mono --profile. With a
local build of xamarin-android on macOS, you can run:
$ mono --profile=log:calls,alloc ./bin/Release/bin/xabuild.exe YourProject.csproj
xabuild.exe is a tool for running MSBuild using your local
xamarin-android working tree. I would also recommend using a Release
build of Xamarin.Android when profiling.
This will create an output.mlpd file in the current directory. To
view its contents:
$ mprof-report output.mlpd
This will display output such as:
Allocation summary
Bytes Count Average Type name
165520032 19363 8548 System.Byte[]
28813336 432701 66 System.String
Method call summary
Total(ms) Self(ms) Calls Method name
139368 1 703 (wrapper runtime-invoke) object:runtime_invoke_void__this__ (object,intptr,intptr,intptr)
132472 132472 287 (wrapper managed-to-native) System.Threading.WaitHandle:Wait_internal (intptr*,int,bool,int)
71685 2 2 Microsoft.Build.BackEnd.RequestBuilder/DedicatedThreadsTaskScheduler:<InjectThread>b__6_0 ()
NOTE: I've hit an error in the past such as:
unhandled profiler event: 0x6f at file offset: 3095192 + 60144 (len: 62655). Sometimes I have just tried again, making sure I'm profiling aReleasebuild.
You can also get stacktrace information:
$ mprof-report --traces output.mlpd > output.txt
I would recomment redirecting this output to a file, as it can generate text well over 100MB!
See the Mono documentation for more details about the profiler.