Comment 127 for bug 1480877

So the latest changes in Lorn's signals6 patch can be summarized as:

1) remove QNetworkManagerEngine::requestUpdate (), which is a public method which can trigger a WiFi scan request to NM.

This method doesn't appear to be called internally by the bearer plugin, so if we think extra WiFi scans are the culprit, there must have been an change to one of our Qt applications which is calling this method. Also as this method wasn't added in the original patch, it's presence can't really be considered a regression. Has anyone attempted to determine if we *are* scanning more often? This could be done manually by running wpa_cli ( as root ), and watching for the frequency of scan events output. It can also be accomplished by looking at the wpa_suppl and/or NM log messages in syslog. And finally, you could also just monitor DBus looking for ScanDone signals from NM.

NOTE - I'm pretty sure this patch won't compile unless this method is also removed from qnetworkmanagerengine.h too, but I haven't tried to build it myself...

 2) check that wiredDevice pointer is valid before using it to call a method

This is the crasher fix when USS/Qt from the PPA gets installed on a desktop. Looks fine to me.

 3) remove most of the logic from the engine's parseConnection() method. This method takes a connection path, and creates a private configuration object, and then based upon the underlying device type, may modify the private configuration instance in a device-specific way before returning it to the caller. The device-specific logic in some cases could have side-effects, such as modifying the global accessPointConfigurations hash table and/or the configuredAccessPoint map.

Again, this chnage looks reasonable to remove, however I don't see how it could have any impact on power. This code only runs during initialization where all existing system connections are loaded, and whenever a new system connection is added ( ie. a user connects to a new AP or APN ).

I'm not sure whether we want to include this the last change if we want to keep the delta as small as possible?