1111407 - Add an easy way to work around logcat drops for local debugging

Status: RESOLVED FIXED

(Core :: mozglue, defect)

Description

[Kartikaya Gupta (email:[e-mail])]

On B2G devices often the best way to debug stuff is via printf_stderr, which comes out via logcat. However logcat uses a circular buffer on-device, and then adb on desktop will pull stuff from that buffer. If there's too much output, the buffer can fill up and stuff will get overwritten before the client can read it, resulting in "adb logcat" missing output. This is a known issue across all android-based devices.

The way to work around this is to log stuff to a file rather than logcat, and then pull the file off the device and look at it instead. It would be nice to have an easy way to do this in local debug builds without having to rewrite the code every time.

Comment 1

[Kartikaya Gupta (email:[e-mail])]

Attachment: Add helper to log to a file

Comment 2

[Kartikaya Gupta (email:[e-mail])]

https://treeherder.mozilla.org/ui/#/jobs?repo=try&revision=0e1e865c157c

Comment 3

[Benoit Girard (:BenWa)]

You can use profile.sh and use the 'log' tab. It provides more information (drawing piepeline) but the major downside is it's not live.

Also being able to dump to a file easily would complement this nicely.

Comment 4

[Kartikaya Gupta (email:[e-mail])]

(I have other stuff to land too, so I can land this with that once the tree is opened)

Comment 5

[Kartikaya Gupta (email:[e-mail])]

https://hg.mozilla.org/integration/b2g-inbound/rev/b8c76c348a69

Comment 6

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/b8c76c348a69