Uh oh!
There was an error while loading. Please reload this page.
[Mono.Android] avoid System.Reflection.Emit usage for common calls - #6657
Merged
Conversation
jonathanpeppersforce-pushed
the
wip-jninativewrapper-sre
branch
from
January 24, 2022 14:30
3991f63 to
eab759fComparejonathanpeppers
marked this pull request as ready for review
January 24, 2022 14:30
Uh oh!
There was an error while loading. Please reload this page.
Contributor
Context: https://github.com/xamarin/xamarin-android/wiki/Blueprint#java-type-registration
Context: b7a368a27667c69117f64be81050403f2d5c8560
Context: https://github.com/xamarin/xamarin-android/pull/4877
Context: https://github.com/xamarin/xamarin-android/pull/4927#issuecomment-875864999
In order for Java code to call C# code,
[`JNIEnv::RegisterNatives()][0] must be invoked, providing an array
of `JNINativeMethod` structures, each of which contains a function
pointer to invoke, kept in `JNINativeMethod::fnPtr`.
Fortunately, delegates marshal as function pointers, and there is a
bunch of `generator`-emitted infrastructure and coordination with
Java Callable Wrappers to eventually obtain a Delegate instance to
provide `JNIEnv::RegisterNatives()`.
There is one deficiency in the `generator`-emitted infrastructure:
it doesn't deal with C# exceptions. However, exceptions "can't"
cross the JNI boundary (see b7a368a2 for an example of the breakage
that results when exceptions do cross the boundary!), except when we
*do* want exceptions to cross the JNI boundary ("improved" IDE first
chance exception experience; see xamarin/xamarin-android#4877).
This "we want to catch exceptions, except when we don't" scenario has
existed since the very beginning. As "the very beginning" predates
[C# 4 exception filters][1], there wasn't a way for `generator`
output to "selectively `catch` exceptions".
We squared this circle by using `System.Reflection.Emit`:
1. During Java Callable Wrapper registration, we lookup the
"marshal method getter" as provided to the `Runtime.register()`
invocation, e.g.
`Android.App.Activity.GetOnCreate_Landroid_os_Bundle_Handler()`.
2.`GetOnCreate_Landroid_os_Bundle_Handler()` is `generator` output,
and contains a `JNINativeWrapper.CreateDelegate()` invocation:
cb_onCreate_Landroid_os_Bundle_ = JNINativeWrapper.CreateDelegate ((_JniMarshal_PPL_V) n_OnCreate_Landroid_os_Bundle_);3.`JNINativeWrapper.CreateDelegate()` uses `System.Reflection.Emit`
to create a new delegate instance which *wraps* the marshal
method `Activity.n_OnCreate_Landroid_os_Bundle()` in a
`try`/*filtered*`catch` block and marshals the exception to Java;
`JNINativeWrapper.CreateDelegate()` effectively returns:
bool _run_catch_if_debugger_not_attached (Exception e) { if (Debugger.IsAttached || !JNIEnv.PropagateExceptions) { JNIEnv.mono_unhandled_exception (e); return false; } return true; } _JniMarshal_PPL_V result = (jnienv, native__this, native_savedInstanceState) => { JNIEnv.WaitForBridgeProcessing (); try { Activity.n_OnCreate_Landroid_os_Bundle_ (jnienv, native__this, native_savedInstanceState); } catch (Exception e) when (_run_catch_if_debugger_not_attached (e)) { AndroidEnvironment.UnhandledException (e); if (Debugger.IsAttached || !JNIEnv.PropagateExceptions) throw; } }; return result;
Again, this was C# 2.0 at the time, so C# 4 exception filters
couldn't be used, thus the need for `System.Reflection.Emit`, so
that [`ILGenerator.BeginExceptionFilterBLock()`][2] could be used
(the support for which is a Mono extension).
After this point, use of `System.Reflection.Emit` was part of the
implicit ABI between Xamarin.Android and binding assemblies. While
`generator`*could* be updated to *itself* emit the `try`/`catch`
block with exception filters, that would only work for binding
assemblies released *after* that `generator` fix.
The `System.Reflection.Emit` wrapper *can't* be skipped without
breaking semantic compatibility, *or* without allowing C# exceptions
to always pass through a JNI boundary, which would be Bad™.
The use of `System.Refleciton.Emit` is a Known Problem™, and
something we'd *like* to remove.
(Hence the [`jnimarshalmethod-gen`][3] explorations…)
With that background out of the way…
Let us turn our attention to the `dotnet new maui` template.
The default MAUI template hits `JNINativeWrapper.CreateDelegate()`
58 times during process startup, and we were wondering if we could
selectively improve these particular invocations, without needing to
re-think the entire "marshal method" infrastructure.
*Partially specialize*`JNINativeWrapper.CreateDelegate()` for the
following delegate types:
*`_JniMarshal_PP_V`*`_JniMarshal_PPI_V`*`_JniMarshal_PPL_L`*`_JniMarshal_PPL_V`*`_JniMarshal_PPL_Z`*`_JniMarshal_PPII_V`*`_JniMarshal_PPLI_V`*`_JniMarshal_PPLL_V`*`_JniMarshal_PPLL_Z`*`_JniMarshal_PPIIL_V`*`_JniMarshal_PPILL_V`*`_JniMarshal_PPLIL_Z`*`_JniMarshal_PPLLL_L`*`_JniMarshal_PPLLL_Z`*`_JniMarshal_PPIIII_V`*`_JniMarshal_PPLLLL_V`*`_JniMarshal_PPLIIII_V`*`_JniMarshal_PPZIIII_V`*`_JniMarshal_PPLIIIIIIII_V`
This is done via use of a T4 template, which generates
`JNINativeWrapper.CreateBuiltInDelegate()`, and
`JNINativeWrapper.CreateDelegate()` is updated to call
`CreateBuiltInDelegate()`:
partial class JNINativeWrapper { static Delegate? CreateBuiltInDelegate (Delegate dlg, Type delegateType) { switch (delegateType.Name) { case "_JniMarshal_PP_V": return … case "_JniMarshal_PPI_V": return … … } return null; } public static Delegate CreateDelegate (Delegate dlg) { … var builtin = CreateBuiltInDelegate (dlg, dlg.GetType (); if (builtin != null) return builtin; … }}
This avoids use of `System.Reflection.Emit` for the specified types.
Other changes:
* Update `TypeManager.GetActivateHandler()` to use
`_JniMarshal_PPLLLL_V` instead of
`Action<IntPtr, IntPtr, IntPtr, IntPtr, IntPtr, IntPtr>`, so the
fast path can be used.
* Added a log message for `adb shell septprop debug.mono.log assembly`:
Falling back to System.Reflection.Emit for delegate type '{delegateType}': {dlg.Method}* I was also able to remove `mono_unhandled_exception_method` from
`JNINativeWrapper` as we already has this value in `JNIEnv`.
~~ Results ~~
Testing `dotnet new maui` with version:
msbuild Xamarin.Android.sln -t:InstallMaui -bl -p:MauiVersion=6.0.200-preview.13.2536
A `Release` build on a Pixel 5 device, total startup time:
| Startup | Average (ms) | Std Err (ms) | Std Dev (ms) || --------- | ------------: | ------------: | ------------: || Before | 1106.3 | 6.919 | 21.879 || After | 1070.8 | 5.686 | 17.980 |
This might save ~35ms on average?
If I time the message for one call, [such as][4]:
I monodroid-timing: Runtime.register: registering type `Microsoft.Maui.MauiApplication, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null`I monodroid-timing: Runtime.register: end time; elapsed: 0s:17::794845
The result is:
| One Call | Average (ms) | Std Err (ms) | Std Dev (ms) || --------- | ------------: | ------------: | ------------: || Before | 23.925 | 0.050 | 0.159 || After | 18.101 | 0.107 | 0.339 |
Saving ~5.8ms for this one call.
`.apk` size difference for `dotnet new android`:
% apkdiff -f before.apk after.apkSize difference in bytes ([*1] apk1 only, [*2] apk2 only):Context: https://github.com/xamarin/xamarin-android/wiki/Blueprint#java-type-registration
Context: b7a368a27667c69117f64be81050403f2d5c8560
Context: https://github.com/xamarin/xamarin-android/pull/4877
Context: https://github.com/xamarin/xamarin-android/pull/4927#issuecomment-875864999
In order for Java code to call C# code,
[`JNIEnv::RegisterNatives()][0] must be invoked, providing an array
of `JNINativeMethod` structures, each of which contains a function
pointer to invoke, kept in `JNINativeMethod::fnPtr`.
Fortunately, delegates marshal as function pointers, and there is a
bunch of `generator`-emitted infrastructure and coordination with
Java Callable Wrappers to eventually obtain a Delegate instance to
provide `JNIEnv::RegisterNatives()`.
There is one deficiency in the `generator`-emitted infrastructure:
it doesn't deal with C# exceptions. However, exceptions "can't"
cross the JNI boundary (see b7a368a2 for an example of the breakage
that results when exceptions do cross the boundary!), except when we
*do* want exceptions to cross the JNI boundary ("improved" IDE first
chance exception experience; see xamarin/xamarin-android#4877).
This "we want to catch exceptions, except when we don't" scenario has
existed since the very beginning. As "the very beginning" predates
[C# 4 exception filters][1], there wasn't a way for `generator`
output to "selectively `catch` exceptions".
We squared this circle by using `System.Reflection.Emit`:
1. During Java Callable Wrapper registration, we lookup the
"marshal method getter" as provided to the `Runtime.register()`
invocation, e.g.
`Android.App.Activity.GetOnCreate_Landroid_os_Bundle_Handler()`.
2.`GetOnCreate_Landroid_os_Bundle_Handler()` is `generator` output,
and contains a `JNINativeWrapper.CreateDelegate()` invocation:
cb_onCreate_Landroid_os_Bundle_ = JNINativeWrapper.CreateDelegate ((_JniMarshal_PPL_V) n_OnCreate_Landroid_os_Bundle_);3.`JNINativeWrapper.CreateDelegate()` uses `System.Reflection.Emit`
to create a new delegate instance which *wraps* the marshal
method `Activity.n_OnCreate_Landroid_os_Bundle()` in a
`try`/*filtered*`catch` block and marshals the exception to Java;
`JNINativeWrapper.CreateDelegate()` effectively returns:
bool _run_catch_if_debugger_not_attached (Exception e) { if (Debugger.IsAttached || !JNIEnv.PropagateExceptions) { JNIEnv.mono_unhandled_exception (e); return false; } return true; } _JniMarshal_PPL_V result = (jnienv, native__this, native_savedInstanceState) => { JNIEnv.WaitForBridgeProcessing (); try { Activity.n_OnCreate_Landroid_os_Bundle_ (jnienv, native__this, native_savedInstanceState); } catch (Exception e) when (_run_catch_if_debugger_not_attached (e)) { AndroidEnvironment.UnhandledException (e); if (Debugger.IsAttached || !JNIEnv.PropagateExceptions) throw; } }; return result;
Again, this was C# 2.0 at the time, so C# 4 exception filters
couldn't be used, thus the need for `System.Reflection.Emit`, so
that [`ILGenerator.BeginExceptionFilterBLock()`][2] could be used
(the support for which is a Mono extension).
After this point, use of `System.Reflection.Emit` was part of the
implicit ABI between Xamarin.Android and binding assemblies. While
`generator`*could* be updated to *itself* emit the `try`/`catch`
block with exception filters, that would only work for binding
assemblies released *after* that `generator` fix.
The `System.Reflection.Emit` wrapper *can't* be skipped without
breaking semantic compatibility, *or* without allowing C# exceptions
to always pass through a JNI boundary, which would be Bad™.
The use of `System.Refleciton.Emit` is a Known Problem™, and
something we'd *like* to remove.
(Hence the [`jnimarshalmethod-gen`][3] explorations…)
With that background out of the way…
Let us turn our attention to the `dotnet new maui` template.
The default MAUI template hits `JNINativeWrapper.CreateDelegate()`
58 times during process startup, and we were wondering if we could
selectively improve these particular invocations, without needing to
re-think the entire "marshal method" infrastructure.
*Partially specialize*`JNINativeWrapper.CreateDelegate()` for the
following delegate types:
*`_JniMarshal_PP_V`*`_JniMarshal_PPI_V`*`_JniMarshal_PPL_L`*`_JniMarshal_PPL_V`*`_JniMarshal_PPL_Z`*`_JniMarshal_PPII_V`*`_JniMarshal_PPLI_V`*`_JniMarshal_PPLL_V`*`_JniMarshal_PPLL_Z`*`_JniMarshal_PPIIL_V`*`_JniMarshal_PPILL_V`*`_JniMarshal_PPLIL_Z`*`_JniMarshal_PPLLL_L`*`_JniMarshal_PPLLL_Z`*`_JniMarshal_PPIIII_V`*`_JniMarshal_PPLLLL_V`*`_JniMarshal_PPLIIII_V`*`_JniMarshal_PPZIIII_V`*`_JniMarshal_PPLIIIIIIII_V`
This is done via use of a T4 template, which generates
`JNINativeWrapper.CreateBuiltInDelegate()`, and
`JNINativeWrapper.CreateDelegate()` is updated to call
`CreateBuiltInDelegate()`:
partial class JNINativeWrapper { static Delegate? CreateBuiltInDelegate (Delegate dlg, Type delegateType) { switch (delegateType.Name) { case "_JniMarshal_PP_V": return … case "_JniMarshal_PPI_V": return … … } return null; } public static Delegate CreateDelegate (Delegate dlg) { … var builtin = CreateBuiltInDelegate (dlg, dlg.GetType (); if (builtin != null) return builtin; … }}
This avoids use of `System.Reflection.Emit` for the specified types.
Other changes:
* Update `TypeManager.GetActivateHandler()` to use
`_JniMarshal_PPLLLL_V` instead of
`Action<IntPtr, IntPtr, IntPtr, IntPtr, IntPtr, IntPtr>`, so the
fast path can be used.
* Added a log message for `adb shell septprop debug.mono.log assembly`:
Falling back to System.Reflection.Emit for delegate type '{delegateType}': {dlg.Method}* I was also able to remove `mono_unhandled_exception_method` from
`JNINativeWrapper` as we already has this value in `JNIEnv`.
~~ Results ~~
Testing `dotnet new maui` with version:
msbuild Xamarin.Android.sln -t:InstallMaui -bl -p:MauiVersion=6.0.200-preview.13.2536
A `Release` build on a Pixel 5 device, total startup time:
| Startup | Average (ms) | Std Err (ms) | Std Dev (ms) || --------- | ------------: | ------------: | ------------: || Before | 1106.3 | 6.919 | 21.879 || After | 1078.8 | 5.438 | 17.197 |
This might save ~35ms on average?
If I time the message for one call, [such as][4]:
I monodroid-timing: Runtime.register: registering type `Microsoft.Maui.MauiApplication, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null`I monodroid-timing: Runtime.register: end time; elapsed: 0s:17::794845
The result is:
| One Call | Average (ms) | Std Err (ms) | Std Dev (ms) || --------- | ------------: | ------------: | ------------: || Before | 23.925 | 0.050 | 0.159 || After | 18.723 | 0.094 | 0.298 |
Saving ~5.8ms for this one call.
`.apk` size difference for `dotnet new android`:
% apkdiff -f before.apk after.apkSize difference in bytes ([*1] apk1 only, [*2] apk2 only):+ 3,390 assemblies/assemblies.blob+ 54 assemblies/assemblies.x86_64.blob- 4 assemblies/assemblies.arm64_v8a.blob- 15 assemblies/assemblies.x86.blob- 65 assemblies/assemblies.armeabi_v7a.blobSummary:+ 3,360 Other entries 0.03% (of 10,526,432)+ 0 Dalvik executables 0.00% (of 7,816,392)+ 0 Shared libraries 0.00% (of 18,414,404)+ 4,096 Package size difference 0.02% (of 21,006,128)
We're looking at a ~4KB size increase for this partial specialization.
[0]: https://docs.oracle.com/javase/8/docs/technotes/guides/jni/spec/functions.html#RegisterNatives[1]: https://docs.microsoft.com/en-us/dotnet/csharp/fundamentals/exceptions/exception-handling#catch-blocks[2]: https://docs.microsoft.com/is-is/dotnet/api/system.reflection.emit.ilgenerator.beginexceptfilterblock?view=net-6.0[3]: http://github.com/xamarin/Java.Interop/commit/c8f3e51a6cfd78bdce89e2429efae4495481f57b[4]: https://github.com/dotnet/maui/blob/bfba62ed796d3416c4fcaa7cfbea86dc8d5e04c2/src/Compatibility/ControlGallery/src/Android/MainApplication.cs |
`dotnet new android` calls `JNINativeWrapper.CreateDelegate()` twice,
while `dotnet new maui` ends up calling it 58 times during startup.
This code path calls System.Reflection.Emit to generate a
`System.Delegate` at runtime to be invoked. After some thought, it is
possible to "hard code" common delegate types and avoid SRE:
private static Delegate CreateBuiltInDelegate (Delegate dlg, Type delegateType)
{
switch (delegateType.Name) {
case nameof (_JniMarshal_PP_V): {
_JniMarshal_PP_V callback = (_JniMarshal_PP_V) Delegate.CreateDelegate (typeof (_JniMarshal_PP_V), dlg.Target, dlg.Method);
_JniMarshal_PP_V result = (jnienv, klazz) => {
JNIEnv.WaitForBridgeProcessing ();
try {
callback (jnienv, klazz);
} catch (Exception e) {
bool filter = Debugger.IsAttached || !JNIEnv.PropagateExceptions;
if (filter && JNIEnv.mono_unhandled_exception != null) {
JNIEnv.mono_unhandled_exception (e);
}
AndroidEnvironment.UnhandledException (e);
if (filter)
throw;
}
};
return result;
}
// etc.
`dotnet new maui`'s startup can be covered if we hardcoded:
_JniMarshal_PP_V
_JniMarshal_PPI_V
_JniMarshal_PPL_L
_JniMarshal_PPL_V
_JniMarshal_PPL_Z
_JniMarshal_PPII_V
_JniMarshal_PPLI_V
_JniMarshal_PPLL_V
_JniMarshal_PPLL_Z
_JniMarshal_PPIIL_V
_JniMarshal_PPILL_V
_JniMarshal_PPLIL_Z
_JniMarshal_PPLLL_L
_JniMarshal_PPLLL_Z
_JniMarshal_PPIIII_V
_JniMarshal_PPLLLL_V
_JniMarshal_PPLIIII_V
_JniMarshal_PPZIIII_V
_JniMarshal_PPLIIIIIIII_V
Then System.Reflection.Emit isn't used at all.
Other changes:
* `TypeManager.GetActivateHandler()` needs to use
`_JniMarshal_PPLLLL_V` instead of `Action<IntPtr, IntPtr, IntPtr,
IntPtr, IntPtr, IntPtr>`, so the fast path can be used.
* Added a log message for `debug.mono.log assembly`:
Falling back to System.Reflection.Emit for delegate type '{delegateType}': {dlg.Method}
* I was also able to remove `mono_unhandled_exception_method` from
`JNINativeWrapper` as we already has this value in `JNIEnv`.
~~ Results ~~
Testing `dotnet new maui` with version:
msbuild Xamarin.Android.sln -t:InstallMaui -bl -p:MauiVersion=6.0.200-preview.13.2536
A `Release` build on a Pixel 5 device, total startup time:
Before:
01-21 11:58:39.030 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s83ms
01-21 11:58:41.297 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s127ms
01-21 11:58:43.429 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s68ms
01-21 11:58:45.702 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s113ms
01-21 11:58:47.906 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s125ms
01-21 11:58:50.082 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s92ms
01-21 11:58:52.297 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s133ms
01-21 11:58:54.465 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s102ms
01-21 11:58:56.673 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s126ms
01-21 11:58:58.848 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s94ms
Average(ms): 1106.3
Std Err(ms): 6.91865433287267
Std Dev(ms): 21.8787060352704
After:
01-21 12:00:33.312 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s61ms
01-21 12:00:35.513 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s79ms
01-21 12:00:37.724 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s85ms
01-21 12:00:39.928 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s83ms
01-21 12:00:42.117 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s60ms
01-21 12:00:44.337 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s59ms
01-21 12:00:46.612 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s106ms
01-21 12:00:48.782 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s47ms
01-21 12:00:51.018 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s75ms
01-21 12:00:53.200 1867 2226 I ActivityTaskManager: Displayed com.companyname.bar/crc6474063b540de74d1e.MainActivity: +1s53ms
Average(ms): 1070.8
Std Err(ms): 5.68584988272544
Std Dev(ms): 17.9802360632137
This might save ~35ms on average?
If I time the message for one call, such as:
01-21 12:14:01.132 29819 29819 I monodroid-timing: Runtime.register: registering type `Microsoft.Maui.MauiApplication, Microsoft.Maui, Version=1.0.0.0,
Culture=neutral, PublicKeyToken=null`
01-21 12:14:01.150 29819 29819 I monodroid-timing: Runtime.register: end time; elapsed: 0s:17::794845
https://github.com/dotnet/maui/blob/bfba62ed796d3416c4fcaa7cfbea86dc8d5e04c2/src/Compatibility/ControlGallery/src/Android/MainApplication.cs
The result is:
Before:
01-21 13:21:22.261 9359 9359 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::868440
01-21 13:21:24.446 9424 9424 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::875159
01-21 13:21:26.639 9497 9497 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::829742
01-21 13:21:28.842 9570 9570 I monodroid-timing: Runtime.register: end time; elapsed: 0s:24::165211
01-21 13:21:31.021 9631 9631 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::976721
01-21 13:21:33.221 9697 9697 I monodroid-timing: Runtime.register: end time; elapsed: 0s:24::237034
01-21 13:21:35.418 9759 9759 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::857346
01-21 13:21:37.585 9821 9821 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::872138
01-21 13:21:39.805 9884 9884 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::840107
01-21 13:21:42.014 9952 9952 I monodroid-timing: Runtime.register: end time; elapsed: 0s:23::723805
Average(ms): 23.9245703
Std Err(ms): 0.0502830551065224
Std Dev(ms): 0.159008981848371
After:
01-21 13:22:28.004 10226 10226 I monodroid-timing: Runtime.register: end time; elapsed: 0s:18::12345
01-21 13:22:30.261 10298 10298 I monodroid-timing: Runtime.register: end time; elapsed: 0s:18::338022
01-21 13:22:32.443 10362 10362 I monodroid-timing: Runtime.register: end time; elapsed: 0s:18::56251
01-21 13:22:34.664 10427 10427 I monodroid-timing: Runtime.register: end time; elapsed: 0s:17::997397
01-21 13:22:36.902 10497 10497 I monodroid-timing: Runtime.register: end time; elapsed: 0s:17::787554
01-21 13:22:39.117 10563 10563 I monodroid-timing: Runtime.register: end time; elapsed: 0s:17::801772
01-21 13:22:41.306 10630 10630 I monodroid-timing: Runtime.register: end time; elapsed: 0s:18::28752
01-21 13:22:43.552 10695 10695 I monodroid-timing: Runtime.register: end time; elapsed: 0s:18::75522
01-21 13:22:45.761 10759 10759 I monodroid-timing: Runtime.register: end time; elapsed: 0s:17::958075
01-21 13:22:47.978 10823 10823 I monodroid-timing: Runtime.register: end time; elapsed: 0s:18::961773
Average(ms): 18.1017463
Std Err(ms): 0.107071213504746
Std Dev(ms): 0.338588906513177
Saving ~5.8ms for this one call.
`.apk` size difference for `dotnet new android`:
> apkdiff -f before.apk after.apk
Size difference in bytes ([*1] apk1 only, [*2] apk2 only):
+ 3,390 assemblies/assemblies.blob
+ 54 assemblies/assemblies.x86_64.blob
- 4 assemblies/assemblies.arm64_v8a.blob
- 15 assemblies/assemblies.x86.blob
- 65 assemblies/assemblies.armeabi_v7a.blob
Summary:
+ 3,360 Other entries 0.03% (of 10,526,432)
+ 0 Dalvik executables 0.00% (of 7,816,392)
+ 0 Shared libraries 0.00% (of 18,414,404)
+ 4,096 Package size difference 0.02% (of 21,006,128)Co-authored-by: Jonathan Pryor <jonpryor@vt.edu>
Uh oh!
There was an error while loading. Please reload this page.
| JNIEnv.WaitForBridgeProcessing (); | ||
| try { | ||
| <#= info.Return ? "return " : "" #>callback <#= info.Signature #>; | ||
| } catch (Exception e) { |
Contributor
There was a problem hiding this comment.
This catch should be updated to:
catch(Exceptione)when(_unhandled_exception(e)){AndroidEnvironment.UnhandledException(e);if(Debugger.IsAttached||!JNIEnv.PropagateExceptions)throw;}jonathanpeppersforce-pushed
the
wip-jninativewrapper-sre
branch
from
January 28, 2022 19:15
9c4da6c to
decce29Comparejonathanpeppers
commented
Jan 28, 2022
MemberAuthor
I think the performance with the latest changes is still probably the same (or very close): Then full displayed: |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for freeto subscribe to this conversation on GitHub.
Already have an account?
Sign in.
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
dotnet new androidcallsJNINativeWrapper.CreateDelegate()twice,while
dotnet new mauiends up calling it 58 times during startup.This code path calls System.Reflection.Emit to generate a
System.Delegateat runtime to be invoked. After some thought, it ispossible to "hard code" common delegate types and avoid SRE:
dotnet new maui's startup can be covered if we hardcoded:Then System.Reflection.Emit isn't used at all.
Other changes:
TypeManager.GetActivateHandler()needs to use_JniMarshal_PPLLLL_Vinstead ofAction<IntPtr, IntPtr, IntPtr, IntPtr, IntPtr, IntPtr>, so the fast path can be used.Added a log message for
debug.mono.log assembly:Falling back to System.Reflection.Emit for delegate type '{delegateType}': {dlg.Method}
I was also able to remove
mono_unhandled_exception_methodfromJNINativeWrapperas we already has this value inJNIEnv.Results
Testing
dotnet new mauiwith version:A
Releasebuild on a Pixel 5 device, total startup time:This might save ~35ms on average?
If I time the message for one call, such as:
https://github.com/dotnet/maui/blob/bfba62ed796d3416c4fcaa7cfbea86dc8d5e04c2/src/Compatibility/ControlGallery/src/Android/MainApplication.cs
The result is:
Saving ~5.8ms for this one call.
.apksize difference fordotnet new android: