Proposal: Add "Take WiFi Lock" button to SeattleOnAndroid

[choksi81]

It should be possible for researchers using local Android devices running their customized installer to make sure the devices stay on WiFi and not drop into power-saving mode. This would ease the development cycle.

Technically, this would involve making the SeattleOnAndroid app take the WiFi Lock when requested by the user, e.g. by tapping a button in the GUI.

[aaaaalbert]

A workaround is available using system tools: Settings > Wireless & networks > Wi-Fi settings > press Menu button and choose "Advanced" > Wi-Fi sleep policy > select "Never".

[aaaaalbert]

Turns out setting the WiFi sleep policy doesn't solve the problem on all devices. I tested by pinging a few different devices from my laptop.

"Never sleep" works on a ZTE Blade phone running Android 2.3.7, and a Galaxy Tab (GT-P3110) running 4.1.2. Both devices have pretty generous WiFi "tails" even in early-standby modes: The Blade remains pingable for 16 minutes (and seems to disassociate from the WiFi after 20 mins); the Galaxy Tab 19 mins / 24 mins.

It doesn't work however on a Sony Tablet S running 4.0.3. Here's the (in)activity pattern I saw when pinging it. * means it replies, _ is silence.

0s          60s        120s        180s        240s        300s        360s
|           |           |           |           |           |           |
**********_*_*_*_*_*________________________*_*_______*_**_*_*___________...
(0)      (1)       (2)                     (3) (4)   (5)     (6)

(0) 50 seconds fully on
(1) 50 seconds toggling between on and off (5s each)
(2) 2 minutes off
(3) 20 seconds toggling
(4) 30 seconds off
(5) 40 seconds toggling
(6) 5 minutes off, then on for 1 second
Not shown in the graph:
(7) at 610 seconds: 3 minutes off
(8) at 780s: 5 seconds on
(9) at 785s: 4 minutes off
(10) at 1100: WiFi access point sends ICMP Redirect message (device probably disassociated from WiFi)

No wonder seash is a pain to use on a device like this.

[aaaaalbert]

I tried with Sensibility Testbed app on the Sony Tablet S with an open-source app named WiFi-Fixer which unfortunately did not fix the problem; Advanced Wifi Lock did manage to keep WiFi on virtually uninterruptedly on this device.

My own attempts adding a user-controlled WiFi lock to our app did not succeed yet, see SensibilityTestbed@7ee9b5c62455f095a8ae5b3908eb1b9eba11deda for details of how I think the implementation should look like.