#8592 HIGH Not Tri: bug or feature? XO hogs CPU trying to find Mesh while already connected to Access Point

[Zarro Boogs per Child]

#8592: bug or feature?  XO hogs CPU trying to find Mesh while already connected to
Access Point
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 Reporter:  thomaswamm   |         Owner:  cjb                              
     Type:  defect       |        Status:  new                              
 Priority:  high         |     Milestone:  Not Triaged                      
Component:  performance  |       Version:  Development build as of this date
 Keywords:               |   Next_action:  reproduce                        
 Verified:  0            |     Blockedby:                                   
 Blocking:  8098         |  
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 Testing beta build 8.2-760.  Found a situation that hogs CPU time. There
 seem to be multiple variations, but I will try to simplify:

 When I resume from suspend (using power button), my XO tries first to find
 a mesh. I am impatient to get back online, so in Neighborhood view I click
 on my WiFi Access Point, which then connects within a few seconds. The
 frame then shows '''both''' the AP icon (connected) '''and''' the Mesh
 icon (still searching for a connection, and pulsating for hours).  Is this
 a bug, or a feature?

 This situation correlates with increased & prolonged CPU usage by sugar-
 shell, shown by 'top' in Terminal.  Even more, multiple repetitions of
 (disconnect AP, then connect AP) will increase CPU usage by sugar-shell
 even more, up to around 50%, which makes the XO more sluggish.

 I also got into a situation (maybe by double-clicking my Access Point
 icon) where both AP icon and Mesh icon were both pulsating grey and trying
 to connect. It sat like that for 2 hours (no change), and 'top' showed 75%
 CPU usage by sugar-shell. Then with some trial & error clicking it went
 almost back to normal (only 10% CPU) and AP connected normally.

 Logs and screenshots coming.  This ticket might help explain #8098.

 By the way, normal behaviour for my XO is to be only connected to my AP
 (and not trying to also connect to Mesh). And sugar-shell normally only
 uses a few % of CPU.  'Normal' logs also coming.

 Now that I understand the behaviour, I can avoid this bug (or feature?). I
 don't know if it will be a nuisance for other users (G1G1 or schools).  It
 can waste CPU cycles.

 Sugar might be wasting CPU cycles while misrepresenting what Network
 Manager is doing (but I am usually wrong).

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Ticket URL: <http://dev.laptop.org/ticket/8592>
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