[Microsoft.Android.Runtime.NativeAOT] Parse debug.mono.log #9824
Conversation
This file contains 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
Context: https://github.com/dotnet/java-interop/blob/9dea87dc1f3052ed0f9499c9858b27c83e7d139e/samples/Hello-NativeAOTFromAndroid/README.md The NativeAOT sample and related `Microsoft.Android.Runtime.NativeAOT` assembly is based in part on the `Hello-NativeAOTFromAndroid` sample in dotnet/java-interop, which contains this comment about Logging: > The (very!) extensive logging around JNI Global and Local > references mean that this sample should not be used as-is for > startup timing comparison. …because `adb logcat` is absolutely *spammed* by LREF and GREF logs. The "solution" in .NET for Android "proper" is to use the `debug.mono.log` system property to control logging. By default, LREF and GREF logs are disabled, but can be enabled by setting the `debug.mono.log` system property property: adb shell setprop debug.mono.log gref # only grefs adb shell setprop debug.mono.log lref,gref # lrefs & grefs adb shell setprop debug.mono.log all # EVERYTHING Begin plumbing support for `debug.mono.log` into `JavaInteropRuntime`. This allows us to e.g. have LREF and GREF logging *disabled by default*, allowing for (somewhat) more representative startup timing comparisons, while allowing these logs to be enabled when needed.
There was a problem hiding this comment.
Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.
Files not reviewed (1)
- src/Microsoft.Android.Runtime.NativeAOT/Microsoft.Android.Runtime.NativeAOT.csproj: Language not supported
src/Microsoft.Android.Runtime.NativeAOT/Android.Runtime.NativeAOT/JavaInteropRuntime.cs
Outdated
Show resolved
Hide resolved
jonathanpeppers
approved these changes
Feb 21, 2025
Change the system property checked from `debug.mono.log`
to `debug.dotnet.log`.
One of the features of `debug.mono.log` is that lref & gref logs
can go to specific files:
adb shell setprop debug.mono.log lref=…/lref.txt,gref=…/gref.txt
Cleanup and retrofit so that this is also supported: introduce a new
`DiagnosticSettings` type to handle system property parsing and
underlying state, along with (possibly common) paths:
adb shell mkdir -p /sdcard/Documents/jonp
adb shell chmod 777 /sdcard/Documents/jonp
adb shell setprop debug.dotnet.log gref=/sdcard/Documents/jonp/jni.txt,lref=/sdcard/Documents/jonp/jni.txt
will send lref & gref logs to `/sdcard/Documents/jonp/jni.txt`.
Or, they can be separate files.
However, the file can only be created once in this circumstance;
if the file already exists, we'll write a log message and then
dump stuff to `adb logcat`:
E NativeAot: Failed to open log file `/sdcard/Documents/jonp/jni.txt`: System.UnauthorizedAccessException: UnauthorizedAccess_IODenied_Path, /sdcard/Documents/jonp/jni.txt
E NativeAot: ---> System.IO.IOException: Permission denied
…
D NativeAot:LREF: +l+ lrefc 1 handle 0x723ff2501d/L from thread ''(1)
…
The introduction of `DiagnosticSettings` allows `debug.dotnet.log`/etc.
to contain additional data, beyond what a `[Flags]` enum could hold.
jonathanpeppers
approved these changes
Feb 24, 2025
Comment on lines
+20
to
+52
| public TextWriter? GrefLog { | ||
| get { | ||
| if (!LogJniGlobalReferences) { | ||
| return null; | ||
| } | ||
| return ((LrefPath != null && LrefPath == GrefPath) | ||
| ? GrefLrefLog ??= CreateWriter (LrefPath) | ||
| : null) | ||
| ?? | ||
| ((GrefPath != null) | ||
| ? CreateWriter (GrefPath) | ||
| : null) | ||
| ?? | ||
| new LogcatTextWriter (AndroidLogLevel.Debug, "NativeAot:GREF"); | ||
| } | ||
| } | ||
|
|
||
| public TextWriter? LrefLog { | ||
| get { | ||
| if (!LogJniLocalReferences) { | ||
| return null; | ||
| } | ||
| return ((LrefPath != null && LrefPath == GrefPath) | ||
| ? GrefLrefLog ??= CreateWriter (LrefPath) | ||
| : null) | ||
| ?? | ||
| ((LrefPath != null) | ||
| ? CreateWriter (LrefPath) | ||
| : null) | ||
| ?? | ||
| new LogcatTextWriter (AndroidLogLevel.Debug, "NativeAot:LREF"); | ||
| } | ||
| } |
There was a problem hiding this comment.
I read through these twice, as it seemed easy to have a typo. I think they are right.
jonathanpeppers
added a commit
that referenced
this pull request
Feb 24, 2025
Context: #9824 With `debug.dotnetlog` support implemented, the lref/gref logging seems sufficient for debugging Java interop (or GC)-related issues. Remove other logging in `NativeAotTypeManager` that seems unnecessary and will yield better startup performance.
This was referenced Feb 24, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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.
Context: https://github.com/dotnet/java-interop/blob/9dea87dc1f3052ed0f9499c9858b27c83e7d139e/samples/Hello-NativeAOTFromAndroid/README.md
The NativeAOT sample and related
Microsoft.Android.Runtime.NativeAOTassembly is based in part on theHello-NativeAOTFromAndroidsample in dotnet/java-interop, which contains this comment about Logging:…because
adb logcatis absolutely spammed by LREF and GREF logs.The "solution" in .NET for Android "proper" is to use the
debug.mono.logsystem property to control logging. By default, LREF and GREF logs are disabled, but can be enabled by setting thedebug.mono.logsystem property property:Begin plumbing support for
debug.mono.logintoJavaInteropRuntime. This allows us to e.g. have LREF and GREF logging disabled by default, allowing for (somewhat) more representative startup timing comparisons, while allowing these logs to be enabled when needed.