[mako] screen corruption/tearing after using the device for medium durations

[Andrew Hayzen]

I had the device on for a day or so and it was 'sleeping' for long periods during this duration.

What happens is the screen is visibly corrupting as things change on the display, eg scrolling up/down the dash or moving the spread. I have taken a short video [0] where you can see the corruption when moving the spread.

I have seen this on both utopic-proposed and rtm-proposed ~3 times in the last few weeks -> last month.

$ system-image-cli -i
current build number: 99
device name: mako
channel: ubuntu-touch/ubuntu-rtm/devel-proposed
alias: ubuntu-touch/ubuntu-rtm/14.09-proposed
last update: 2014-10-19 07:24:09
version version: 99
version ubuntu: 20141019
version device: 20141017.2
version custom: mako-1.1

0 - https://drive.google.com/file/d/0B3XynHVKfrvMNm00QllIWG9DY28

[Daniel van Vugt (vanvugt)]

Medium at most I think.

It's a very rare bug. Most mako owners never see it. And even when you do, no functionality is lost.

[Andrew Hayzen (ahayzen)]

FYI we've seen this on two further separate mako devices this morning, one of them was on #102 rtm-proposed and had an uptime 2 days+.

[Michael Hall (mhall119)]

I've had this all the way up to RTM #12. Just installed RTM #13 and will report if it's still there

[kevin gunn (kgunn72)]

follow on from an irc chat, mhall seeing this recently with uReadIt app (his most used)
if anyone sees it, it'd be useful to know if a lightdm restart corrects the problem or not.

[Daniel van Vugt (vanvugt)]

It does seem likely we're probably doing something wrong in our Android fencing code but I'm slightly suspicious of the mako hardware too.

See also; another mako corruption issue I found recently: bug 1406725. It's a different bug because it's a different kind of corruption occurring under different circumstances to this.

[Michael Hall (mhall119)]

I had the graphics issue again and restarting lightdm fixed it

http://paste.ubuntu.com/9752519/ shows RAM usage before and after

[Andrew Hayzen (ahayzen)]

FYI, I had this again on the latest rtm-proposed image and I can also confirm that restarting lightdm fixed the issue.

I see a similar drop in memory usage before and after [0], but this could just be due to apps closing (I had gmail and telegram open before restarting lightdm)

0 - http://pastebin.ubuntu.com/10673351/

$ system-image-cli -i
current build number: 214
device name: mako
channel: ubuntu-touch/ubuntu-rtm/devel-proposed
alias: ubuntu-touch/ubuntu-rtm/14.09-proposed
last update: 2015-03-23 01:43:53
version version: 214
version ubuntu: 20150312
version device: 20150116
version custom: mako-1.1

[Michał Sawicz (saviq)]

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