How to use ProtoLog.d()/v()/i()/w()/e()/wtf() in ProtoLog.java?

[JustinHu1983]

For my own code, can I use ProtoLog.d()/v()/i()/w()/e()/wtf() in ProtoLog.java to output logs? Once I call ProtoLog.d()/v()/i()/w()/e()/wtf() to output logs, does it output in perfetto format?

[LalitMaganti]

For my own code, can I use ProtoLog.d()/v()/i()/w()/e()/wtf() in ProtoLog.java to output logs?

I mean it's an API which works so in that respect you can use it. Whether it's useful depends on your usecase.

Once I call ProtoLog.d()/v()/i()/w()/e()/wtf() to output logs, does it output in perfetto format?

Tehcnically yes though Protolog was only designed for helping debug and analyse window transitions using Winscope. Documentation for this is tat https://source.android.com/docs/core/graphics/winscope/capture/adb#capture-adb-protolog and https://source.android.com/docs/core/graphics/winscope/analyze/protolog

Note however that the Perfetto UI has no support for protolog, it will not show up in our UI at all. The trace processor puts it in the protolog table but that's it. In some sense, the fact that Winscope/Protolog use perfetto traces is an implementation detail of Winscope. Protolog is meant essentially exclusively for consumption by folks using Winscope.

[JustinHu1983]

I have following query,

1. Tehcnically yes though Protolog was only designed for helping debug and analyse window transitions using Winscope. --- What was the original intention of this design? Was it to solve the problem of WinScope's high-frequency log output?
2. Base on 1), can I use Protolog for other high-frequency log output domain/ module? such as systemUI.
3. the Perfetto UI has no support for protolog --- any suggestion how to view and analyze Protolog content? with traceconv?

[LalitMaganti]

What was the original intention of this design? Was it to solve the problem of WinScope's high-frequency log output?

Yes it was only designed for Winscope.

Base on 1), can I use Protolog for other high-frequency log output domain/ module? such as systemUI.

You can do whatever you want, whether it will be useful is another question.

the Perfetto UI has no support for protolog --- any suggestion how to view and analyze Protolog content? with traceconv?

There is no other viewer or supported experience other than Winscope. Any other tool you use is at your own risk and will not be supported by us.

[JustinHu1983]

designed for Winscope. --- to solve what kind of problem? or What was the original intention of this design?

for Winscope, how to view Protolog?

[LalitMaganti]

Please read https://source.android.com/docs/core/graphics/winscope/overview. It's all documented there. We don't own nor are we responsible for Winscope, again we only are a base layer. If you have questions, you should get support through the channels Winscope provides, we are unable to provide any support for it.

[JustinHu1983]

Ok, thanks for your reply