1022586 - [tarako only] kill the homescreen app when memory low, since Bug 1014272 - [tarako only] Run the homescreen in process

Status: RESOLVED FIXED

(Firefox OS Graveyard :: Gaia::System, defect)

Description

[ying.xu]

since Bug 1014272 - [tarako only] Run the homescreen in process.
homscreen app is launched in b2g process. that causes it can not be killed by LMK.

But we do need homescreen exited when running at background and memory low(receiving Memorypressure event) to free some memory for foreground apps(mostly, 3rd parties apps)

Comment 1

[Naoki Hirata :nhirata (please use needinfo instead of cc)]

I think we should be careful not to kill homescreen too often, or else we defeat the purpose of bug 1014272.

Comment 2

[James Zhang (Spreadtrum)]

(In reply to Naoki Hirata :nhirata (please use needinfo instead of cc) from comment #1)
> I think we should be careful not to kill homescreen too often, or else we
> defeat the purpose of bug 1014272.

Yes, we can kill it before foreground app killed, to pass top 3rd-party test case.

Comment 3

[ying.xu]

please refer 
https://bugzilla.mozilla.org/show_bug.cgi?id=1014272#c40

Comment 4

[ying.xu]

Attachment: kill-homscreen-onlowmemory.patch

patch to kill homescreen
Please review

Comment 5

[(inactive after 6/18) Alive Kuo [:alive]]

Comment on attachment 8438930 [details] [diff] [review]
kill-homscreen-onlowmemory.patch

Review of attachment 8438930 [details] [diff] [review]:
-----------------------------------------------------------------

Please do in homescreen_launcher and remove the dump.
More: you will end up adding many handlers if render() is called many times.
This kind of event listener should be in its manager not in instance level.

Comment 6

[ying.xu]

Attachment: PR@v1.3t

please review again

Comment 7

[Gregor Wagner [:gwagner]]

Joe, can you do triage here?

Comment 8

[(inactive after 6/18) Alive Kuo [:alive]]

Comment on attachment 8440596 [details] [review]
PR@v1.3t

See comments

Comment 9

[ying.xu]

Attachment: new pr@v1.3t, updated as Comment 8

Comment 10

[[:fabrice] Fabrice Desré]

Ying, why did you flag me?

Comment 11

[ying.xu]

(In reply to Fabrice Desré [:fabrice] from comment #10)
> Ying, why did you flag me?

Oh, I wonder do you have any suggestions about this?

Comment 12

[James Zhang (Spreadtrum)]

Ying, please set review? flag and add Fabrice.
Shrink more memory for foreground app with big memory usage.

Comment 13

[ying.xu]

v1.3t
https://github.com/mozilla-b2g/gaia/commit/45382bbccebe19b786cb1a7c4c03516f20230e8f

Comment 14

[Joe Cheng [:jcheng] (please needinfo)]

already landed on 1.3T, 1.3T+

Comment 15

[Danny Liang [:dliang]]

Hi James, by yesterday's discussion, please help to update the result of monkey test about black homescreen issue and see if the issue related to homescreen was killed by memory pressure event.

Comment 16

[James Zhang (Spreadtrum)]

Danny, you can revert this commit and try to reproduce it. You don't need monkey test.

Comment 17

[Danny Liang [:dliang]]

(In reply to James Zhang (Spreadtrum) from comment #16)
> Danny, you can revert this commit and try to reproduce it. You don't need
> monkey test.

After revert below commit, I cannot reproduce the black homescreen issue.

commit 4ab1432ed292b306cf52d005a2b312ae5bc95d66
Author: ying.xu <[e-mail]>
Date:   Mon Jun 16 17:10:19 2014 +0800

    Bug#1022586 kill the homescreen app when memory low
    
    [self test   ] kill and restore ok

Comment 18

[yang.zhao]

(In reply to Danny Liang [:dliang] from comment #17)
> (In reply to James Zhang (Spreadtrum) from comment #16)
> > Danny, you can revert this commit and try to reproduce it. You don't need
> > monkey test.
> 
> After revert below commit, I cannot reproduce the black homescreen issue.
> 
> commit 4ab1432ed292b306cf52d005a2b312ae5bc95d66
> Author: ying.xu <[e-mail]>
> Date:   Mon Jun 16 17:10:19 2014 +0800
> 
>     Bug#1022586 kill the homescreen app when memory low
>     
>     [self test   ] kill and restore ok
Hi,Danny
    I think maybe it have some risk if the homescreen couldn't be killed.Once some issues occur in homescreen app, users have to recover the phone by restarting it.

Comment 19

[Danny Liang [:dliang]]

(In reply to yang.zhao from comment #18)
> (In reply to Danny Liang [:dliang] from comment #17)
> > (In reply to James Zhang (Spreadtrum) from comment #16)
> > > Danny, you can revert this commit and try to reproduce it. You don't need
> > > monkey test.
> > 
> > After revert below commit, I cannot reproduce the black homescreen issue.
> > 
> > commit 4ab1432ed292b306cf52d005a2b312ae5bc95d66
> > Author: ying.xu <[e-mail]>
> > Date:   Mon Jun 16 17:10:19 2014 +0800
> > 
> >     Bug#1022586 kill the homescreen app when memory low
> >     
> >     [self test   ] kill and restore ok
> Hi,Danny
>     I think maybe it have some risk if the homescreen couldn't be
> killed.Once some issues occur in homescreen app, users have to recover the
> phone by restarting it.

Without reverting the commit, switch application and wallpaper are black easily. By test on launch camera under background music, the black screen issue will be reproduced in 10 minutes.
That's why I recommend to revert it first.