Can't select rows via checkboxes anymore

[pyricau]

I'm not sure when this changed but up until recently I was able to select a time span and then checkboxes would appear on every row, and checking those checkboxes would add tabs to the bottom sheet that shows "Current selection". This is a great way to figure out where we spend time in various states, as well as how long each process is running across CPUs during that time span, etc.

As of today, it looks like the checkboxes are gone, I can't select rows anymore.

[LalitMaganti]

I cannot reproduce this:

The checkboxes show up fine and seem to do the right thing when I click on them (add/remove selections).

[pyricau]

It.. just came back?!

[pyricau]

oh, I know. If I manually select a span with click and slide the mouse, it works. But if I click on a span, press M, then click on the little triangles, the checkboxes don't show. They used to.

[LalitMaganti]

Thanks for the clarification: I think then that change is somewhat intended. We were discussing internally that going from selection of an interval in the top bar -> area selection of tracks required a bunch of convoluted logic behind the scenes in the UI and was blocking improvements we want to make to how selection works.

We figured it was a very rarely used feature (after discussing with a bunch of internal users) and so we decided to (at least temporarily) stop coupling the two and unblock the other improvements. In fact in the multiple weeks this change has been in autopush/canary, you are the first person to notice this :)

@stevegolton is out this week but we can discuss when he is back if there's any way to bring it back easily in the post-refactoring world and/or some UX we can do to easily start an area selection from an interval selection.

[pyricau]

It's definitely convoluted, and I accidentally stumbled on this, but it's a core part of my workflow now :) . I just didn't have anything to dig in lately.

The whole thing was definitely awkward, and even clicking the checkboxes on 8 CPU rows is very prone to error (if you mis click you lose the whole selection).

The thing I really want is being able to select an exact span rather than manually have to click and drag, which requires zooming in a lot and getting the mouse select exactly right.

The main two usages are:

1. For a given trace section span, I want to visualize the sum of time spent in each cpu state
2. For a given trace section span, I want to know how much CPU time is spent per process and per thread.

[LalitMaganti]

The whole thing was definitely awkward, and even clicking the checkboxes on 8 CPU rows is very prone to error (if you mis click you lose the whole selection).

So when I was saying "blocking improvements we want to make to how selection works", I was meaning exactly this :) We think that we can do a better job at giving people the information they are looking for without going through the awkward UX you have to go to today.

For a given trace section span, I want to visualize the sum of time spent in each cpu state

BTW there's already a better way to do this. If you click on a slice, you'll get the breakdown of the slice by cpu state:

For a given trace section span, I want to know how much CPU time is spent per process and per thread.

Yup similar to the above, we should have a pre-defined, opinionated aggregation for this and include it as another tab (named something like "other CPU consumers" or similar).

[stevegolton]

We did indeed change this behaviour back in June (it probably only recently landed on the stable channel). I believe this was the commit.

The main thing that changed is area notes (what you create when you press M) no longer store a list of tracks, they just represent a start and end time. This change was made, as Lalit already mentioned, so that we could make some improvements to the arcitecture surrounding selection, and this feature was deemed to be fairly low priority so unfortunately it got removed.

What we still do have, and is a core feature of the UI, are are selections (this is what you create when clicking and dragging). Rather than making a span note, I think the feature you really need (correct me if I'm wrong) is a hotkey that allows you to turn the selected slice into an area selection. This would allow you to check the checkboxes.

Here is a demo (currently bound to 'L').

As you noted the selection management (click anywhere and lose the selection) leaves something to be desired in the UX department. Improving this is on our list.