1218658 - [Woodduck][System][Homescreen]Cannot return to homescreen when launching two Apps rapidly almost at the same time

Status: RESOLVED WONTFIX

(Firefox OS Graveyard :: Gaia::System::Task Manager, defect, P1)

Description

[Keith Tu]

Attachment: import-no-active-app.tar.gz

Description:
Cannot return to homescreen when launching two Apps rapidly almost at the same time.
No active App currently.
See the attachment to get more details.

Reproduce Steps (5%):
1. Try to launch two Apps at the same time rapidly (using two fingers pressing two Apps - Contacts and Camers)
2. Hold home button
3. Remove Contacts first and Camera last
4. Black Screen still -- KO (see index.png in attachment)
5. Press Home button to try to go back homescreen but still hold in black screen -- KO (see index.png in attachment)

Analysis:
1. No active App currently (see no-active-app.png)
2. See the logs in console (see console.log and console.log.png)

Comment 1

[Gregor Wagner [:gwagner]]

Can we get a video?

Comment 2

[Gregor Wagner [:gwagner]]

Just to make sure: this is 2.5 on an aries device?

Comment 3

[Keith Tu]

We found the issue on Woodduck branch.
The vedio will be updated by wei.deng.
He'll release a download link.

Comment 4

[Keith Tu]

Here is the video download link:
http://pan.baidu.com/s/1bnlvXsb

Comment 5

[Wesly Huang (EPM)]

Hi Etienne:

Sorry for bothering again, but do you think you'll be suitable to help chech the log here, from Gaia system point of view? Or suggest me a right person?

Thanks!

Comment 6

[Wesly Huang (EPM)]

Also put the video in comment#4 to Gdrive: https://drive.google.com/open?id=0Bz6aW3cbHgB8NG1IVFBoYzBrRjg

Comment 7

[Gregor Wagner [:gwagner]]

Thats the old homescreen. Kevin, can you take a look?

Comment 8

[Etienne Segonzac (:etienne)]

(In reply to Wesly Huang (TAM) from comment #5)
> Hi Etienne:
> 
> Sorry for bothering again, but do you think you'll be suitable to help chech
> the log here, from Gaia system point of view? Or suggest me a right person?

It's hard to check the logs since I don't have the code where the debug statements were added :)

* I don't think this is homescreen-related, even when we get to webapps-launch at the same time the WindowManager should do the right thing and open both apps one after the other. And couldn't find a regression in this area.
* Even if something goes wrong and there's no active app pressing "home" should work and display the homescreen
* Might be an issue with the old TaskManager, can we reproduce this on master?

Comment 9

[Keith Tu]

BTW, It took me about 2 hours to reproduce the issue in order to take down the video.
For our PA, 5% reproduce.
If you want to check where the log/debug statements were added, you can ask Wesly for a Woodduck SW to have a check since we've sent him 2 days ago.

Comment 10

[Kevin Grandon :kgrandon]

(In reply to Gregor Wagner [:gwagner] from comment #7)
> Thats the old homescreen. Kevin, can you take a look?

This is most certainly a problem with the system app and the not the home screen. The home screen just requests opening of apps.

Like Etienne said, let's see if we can reproduce this issue on master.

Comment 11

[Keith Tu]

The similar race condition issue:
https://bugzilla.mozilla.org/show_bug.cgi?id=1220028

Comment 12

[Wesly Huang (EPM)]

(Thanks Etienne and Kevin's comment!)

Hi Norry:

This issue was found in woodduck w/ 5% repro. rate per partner (MTK build), but we are more interested in knowing if this can be seen in master per comment#8 & comment#10 as above, would you help verify? 

Thanks!

Comment 13

[zouyi(Leave from Mozilla)]

Hi Wesly,
This bug can't be repo on flame master & Aries Master with 100 attempts on each device(flame/aries). It can return to home screen successfully based on the STR of comment 0. Please see video: Arieskk_master.3gp
Rate: 0/100

FlameKK master 512MB(Unaffected)
Build ID               20151101150206
Gaia Revision          91cac94948094cfdcd00cba5c6483e27e80cb3b0
Gaia Date              2015-10-28 20:32:15
Gecko Revision         https://hg.mozilla.org/mozilla-central/rev/96377bdbcdf3e444a22aeaa677da696243b00d98
Gecko Version          45.0a1
Device Name            flame
Firmware(Release)      4.4.2
Firmware(Incremental)  eng.cltbld.20151101.183234
Firmware Date          Sun Nov  1 18:32:48 EST 2015
Bootloader             L1TC000118D0

AriesKK master(Unaffected)
Aries KK eng
Build ID               20151101012023
Gaia Revision          91cac94948094cfdcd00cba5c6483e27e80cb3b0
Gaia Date              2015-10-28 20:32:15
Gecko Revision         https://hg.mozilla.org/mozilla-central/rev/96377bdbcdf3e444a22aeaa677da696243b00d98
Gecko Version          45.0a1
Device Name            aries
Firmware(Release)      4.4.2
Firmware(Incremental)  eng.worker.20151101.004008
Firmware Date          Sun Nov  1 00:40:17 UTC 2015
Bootloader             s1

Comment 14

[zouyi(Leave from Mozilla)]

Attachment: Arieskk_master.3GP

Comment 15

[Wesly Huang (EPM)]

Thanks ZouYi's effort on it!

Then given master's result, the late phase of 2.0/2.0m, and the STR in comment 0, we'll lower down this issue's priority until new input.

Comment 16

[BMO Automation]

Firefox OS is not being worked on