1478856 - about:performance changes its sort order on every refresh

Status: RESOLVED FIXED

(Toolkit :: Performance Monitoring, enhancement)

Description

[(no longer active)]

The new about:performance page looks really great!  But it's hard to use since it changes its sort order on every refresh.  It seems that the data displayed is unsorted.  It would be nice to sort it in a specific order.

Comment 1

[Florian Quèze [:florian]]

(In reply to :Ehsan Akhgari from comment #0)
> The new about:performance page looks really great!

Thanks!

> But it's hard to use
> since it changes its sort order on every refresh.  It seems that the data
> displayed is unsorted.  It would be nice to sort it in a specific order.

The sorting needs improvements indeed, I was going to file a bug to change it :-).

It is actually already sorted. The order is currently based on how many runnables were dispatched during the last 10s (this information isn't displayed, the table displays the total since page load, and the last 2s). The reason for doing this is that it makes misbehaving pages bubble up to the top almost immediately, but a page that was misbehaving recently and has stopped won't go down in the list immediately.

The current order is random for pages that have had the same number of runnables in the last 10s (typically 0 for the bottom of the list which moves around a lot).

Comment 2

[Florian Quèze [:florian]]

Attachment: Patch

Comment 3

[(no longer active)]

(In reply to Florian Quèze [:florian] from comment #1)
> It is actually already sorted. The order is currently based on how many
> runnables were dispatched during the last 10s (this information isn't
> displayed, the table displays the total since page load, and the last 2s).
> The reason for doing this is that it makes misbehaving pages bubble up to
> the top almost immediately, but a page that was misbehaving recently and has
> stopped won't go down in the list immediately.

Hmm, but doesn't that ordering essentially change every 10 seconds completely?  I think that is the problem I was seeing (hard to say exactly since this number isn't displayed as you said.)  Based on your description, it's not obvious to me if the current patch changes the behavior I was complaining about (but perhaps I'd need to test it in practice...)

> The current order is random for pages that have had the same number of
> runnables in the last 10s (typically 0 for the bottom of the list which
> moves around a lot).

FWIW while testing this, I only had two tabs open, one about:performance, one the Facebook login page, and there were entries for some Firefox internals.  I doubt that I was seeing this part of the problem...

Comment 4

[:Felipe Gomes (needinfo for replies!)]

Comment on attachment 8995549 [details] [diff] [review]
Patch

Review of attachment 8995549 [details] [diff] [review]:
-----------------------------------------------------------------

You'll probably want to iterate more on this over time, so I'd change the responsibility from sorting to outside of getCounters, i.e. make a separate sorting function that the caller should invoke

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/74c9a7939000
make the about:performance sort order more stable, r=felipe.

Comment 6

[Raul Gurzau (:RaulG)]

https://hg.mozilla.org/mozilla-central/rev/74c9a7939000

Comment 7

[Martin Thomson [:mt:]]

This is the most obvious problem I see with about:performance myself.  In particular, the "close tab" button jumps about too much.  Could this sort based on a long-running tally rather than over just the last cycle?

Comment 8

[Florian Quèze [:florian]]

(In reply to Martin Thomson [:mt:] from comment #7)
> This is the most obvious problem I see with about:performance myself.

This bug here is fixed. Before the patch from this bug, the order as moving at every refresh, making it hard to even read what was displayed.

> In
> particular, the "close tab" button jumps about too much.

I agree that it's extremely annoying to have the sort order change when one is about to click the close button. It closed the wrong tab a couple times, I'll file a new bug.

> Could this sort
> based on a long-running tally rather than over just the last cycle?

The sort order is already based on the last 10s of data (vs the displayed data is the last 2s). I think any change in the order (even if it's every 30s) will be annoying when attempting to interact with the close buttons.

Comment 9

[Florian Quèze [:florian]]

(In reply to Florian Quèze [:florian] from comment #8)

> > In
> > particular, the "close tab" button jumps about too much.
> 
> I agree that it's extremely annoying to have the sort order change when one
> is about to click the close button. I closed the wrong tab a couple times,
> I'll file a new bug.

I filed bug 1502080.