Show tooltips on each track and Synthetic TrackEvent

[wangjiyang]

Hi Perfetto team,
Perfetto users need a lot of background knowledge of what each perfetto track meaning. This knowledge may only exists in developers develop perfetto producer/perfetto ui. Such developers may take a lot of time to explain what each track really meaning.

Is it possible to add a tooltip reminding, to ease users lookup documentations and asking developers for help.

[aMayzner]

We are generally in agreement, that it would be good to have additional information on the tracks, to explain the names and details of what data does the track show. Unfortunately most of our tracks (for example the ones you pointed at) are based on atrace tracks - which means there is no point in the UI in which we create them and can add a detailed documentation or better names. The only way would be to create a map of track name to explanation, but so far there has not been a need for it. For example, for the track that you pointed at, it should be a matter of simply googlying what mem.rss is.

We will most likely fix this issue by creating better documentation - it's high on our priority list to create a step by step guides, better FAQ and explanations of how to debug your issues using Perfetto.

[wangjiyang]

@aMayzner Would you consider this feature for TrackEvents? since it's generated totally under controll and such mapping can be imported to sqlite virtual table and perfetto ui can take advantage of this information.

[LalitMaganti]

I think we could consider adding some sort of description to the track event protos certainly. Patches for this welcome.