4sec(!!) activity launch splash screen regression, no longer fast enough to be helpful.

[garycmartin]

joyride-2233, XO-B4

Over the last week or two the (great) activity launch splash screens have regressed in speed to the point they are no longer helpful :-(

I'm now back to accidentally launching multiple instances of activities as it's taking ~4 seconds after clicking to show any kind of UI launch splash screen response (so I think I miss-clicked).

FWIW: I genuinely rate UI launch feedback latency (actually any UI feedback latency, but I digress) as more important than shaving a few of seconds off the total launch time. Fast UI feedback provides an illusion of speed to the operator (iPhone is a good example of this trick done well).

[marco]

I suspect datastore performance. Can you please try to move away /home/olpc/.sugar/default/datastore and see if you get immediate feedback back? Also please paste the results of an ls -l of that directory. Thanks.

[marco]

It would be really useful if you could do the test I suggested.

[garycmartin]

Sorry for delay. OK, so I've just: Moved my data and datastore directories out of the way; rebooted; checked that journal was showing empty; allowed the neighbourhood to finish populating; checked top to make sure there are no cpu intensive processes. Using Paint activity as the test case, after clicking in the home view ring, or resuming from the Journal (once it's been launched once already), it's taking 3 seconds before the launch splash screen starts to display. So perhaps a slight improvement after removing all Journal entries, but not much. Anything else you want me to try?

Observation (with near empty Journal and repeated launch tests): Some activities are consistently worse than others. 5sec=TurtArt. 4sec=Geoquiz, Implode. 3sec=Pippy, Paint, Moon. 2sec=Record, Words, Write, Chat, EToys. 1sec=Terminal, Log, Analyse, BlockParty. Why should the launch splash screen take any less or more time dependant on activity?

[kimquirk]

Not a blocker, but we will still consider a fix for 8.2.

[marco]

Can you verify with the latest build? This *might* have been caused by a dbus breakage which has been fixed.

[garycmartin]

Testing on joyride-2301, the launch splash screen latency is now much better. Testing a range of activities (including those mentioned above), all show a delay of no more than 1sec from initial click before the launch splash screen draws. Looks like it might have been the dbus breakage. I think this is now fast enough for 8.2.0 to be closed, if other testers see the same improvement.

[mtd]

In joyride-2318 I see the launch splash screen in between ~1 and ~2 seconds after clicking on the ring activity icon (tested with Pippy and Paint).

[garycmartin]

Testing in joyride-2444 and 8.2-760 this seems to have regressed even further, or fallen out the tree altogether. I'm seeing no UI feedback for about 7 seconds in one case now, with the quickest UI feedback time coming from Terminal (3sec before launch window shows). This when combined with #7876 is a disaster waiting for a class full of excited kids :-(

[marco]

Can you provide logs please? Do you see any process taking a lot of cpu in top?

[garycmartin]

OK. Think I have it... Tested launching times while connected jabberd server (about ~10 buddies showing, maybe 2 visible activities share icons) and with jabberd server removed (just mesh icons and ~6 APs showing in Neighborhood). Allowing time for the buddy appearances to stabilise before testing when connected to jabberd (i.e no more visual buddy updates) gave the 5-8sec delay before launch window result. Removing the jabberd server setting, and restarting, the launch window appears 1-2sec after clicking.

With just one XO here I can't tell if it's jabberd vs salute, X number of buddies, N shared activities, or some combination that brings the launch window appearance time to it's knees. I'll try and keep an eye on the Neighborhood and report if I see a pattern.

Hope that helps others test.

[garycmartin]

Let me up that count of folks on the jabberd server (xochat.org), it's closer to ~26 buddy icons, and I can see 4 shared activities (chat, paint, record, and speak).

[marco]

Thanks a lot for tracking this down garycmartin.

[daf]

This suggests that some sugar.presence calls are taking a long time.

[marco]

garycmartin, if you are around can you check if your are still seeing a big delay right now? I see "only" a 1 second delay when connected to xochat.org.

The delay is when we switch the active activity and could be due to several different things.

[garycmartin]

Replying to marco:

garycmartin, if you are around can you check if your are still seeing a big delay right now? I see "only" a 1 second delay when connected to xochat.org. The delay is when we switch the active activity and could be due to several different things.

Testing (with TurtleArt-10) is currently giving me an average 5sec delay before launch window shows. About 19 buddies showing and no shared activity icons. Uploading a screen shot of the Neighborhood view for reference.

[garycmartin]

TurtleArt-10 launchwindow appearance latency 5sec (1-2sec if no buddies showing)