When launching B2G desktop client using mozrunner, there is an excessive amount of logging output to the console. Most of this appears to be related to Marionette. When using this in combination with running tests, it's very difficult to see the test results in the console. The following is just what's generated during launch. If tests are running it appears that all Marionette logs are output to the console. $ mozrunner --binary=/Users/dhunt/Desktop/mozilla-b2g18/B2G.app Starting: /Users/dhunt/Desktop/mozilla-b2g18/B2G.app/Contents/MacOS/b2g -profile /var/folders/5_/9gz0dv9s51q2shxc8hg62j200000gn/T/tmpeHyBdR.mozrunner Starting b2g-bin Running: /Users/dhunt/Desktop/mozilla-b2g18/B2G.app/Contents/MacOS/b2g-bin -profile /Users/dhunt/Desktop/mozilla-b2g18/B2G.app/Contents/MacOS/gaia/profile 1365002735841 Marionette INFO MarionetteComponent loaded 1365002735843 Marionette INFO marionette enabled 1365002735875 Marionette INFO marionette initializing at final-ui-startup ###################################### forms.js loaded ############################### browserElementPanning.js loaded ######################## BrowserElementChildPreload.js loaded [AccessFu] INFO attach ###################################### forms.js loaded ############################### browserElementPanning.js loaded ######################## BrowserElementChildPreload.js loaded XXX FIXME : Got a mozContentEvent: system-message-listener-ready XXX FIXME : Got a mozContentEvent: accessibility-screenreader ###################################### forms.js loaded ############################### browserElementPanning.js loaded ######################## BrowserElementChildPreload.js loaded ###################################### forms.js loaded ############################### browserElementPanning.js loaded ######################## BrowserElementChildPreload.js loaded

Jonathan: Any ideas how I might reduce this log level when launching via mozrunner?

This is all stdout spew from the B2G process, which is printed to stdout by default by mozprocess' ProcessHandler: https://github.com/mozilla/mozbase/blob/master/mozprocess/mozprocess/processhandler.py#L832 If you want to get rid of it, you could create a subclass of ProcessHandler that defines processOutputLine so you avoid the default stdout dump, and then pass this new class as the process_class kwarg in mozrunner's ctor.

Thanks for the info, based on this I was able to pass a 'processOutputLine' argument with an object that will basically ignore all output passed to it. I'm not sure if this is the best approach, but it does work well for me. Could you provide feedback?

Comment on attachment 735664 [details] [diff] [review] Redirect process output to null. v1.0 Review of attachment 735664 [details] [diff] [review]: ----------------------------------------------------------------- I think this is generally the right approach, but I worry about ignoring all the output. When debugging test failures, having access to the output would likely sometimes be useful. We may want to write all the output to a file that could be examined later at leisure.

If we pass 'logfile' in kp_kwargs then this will be written to file. I could write to simply 'gecko.log' unless you have some other suggestion?

sounds reasonable

Comment on attachment 738020 [details] [diff] [review] Redirect process output to null and append to log file. v2.0 Review of attachment 738020 [details] [diff] [review]: ----------------------------------------------------------------- Eventually we may want a command-line arg to specify the logfile name, but this is fine for now, we can add that later if it turns out to be needed.

Landed on inbound: https://hg.mozilla.org/integration/mozilla-inbound/rev/dbc28a463297

Uplifted to b2g18: https://hg.mozilla.org/releases/mozilla-b2g18/rev/30dea6c6bedf