#2654 HIGH Trial-3: Sugar Shell is offering D-Bus services in the UI loop

[Zarro Boogs per Child]

#2654: Sugar Shell is offering D-Bus services in the UI loop
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  Reporter:  tomeu   |       Owner:  tomeu  
      Type:  defect  |      Status:  new    
  Priority:  high    |   Milestone:  Trial-3
 Component:  sugar   |     Version:         
Resolution:          |    Keywords:         
  Verified:  0       |  
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Comment (by AlbertCahalan):

 Replying to [comment:4 tomeu]:

 > Well, all services offered today by the Shell are fast enough. But this
 could change some day. Any service that uses the network is potentially
 very slow and shouldn't be called synchronously by an UI thread or by
 another D-Bus service.

 Slow network things are perfectly OK to do from the UI loop. You set the
 network file descriptor to non-blocking, then use poll() or select() to
 see when you can read/write without blocking.

 > But anyway, the real problem here are dead locks. Having the same
 process/thread/eventloop doing the UI and at the same time providing
 generic services to activities and other services is going to cause dead
 locks.

 Sure you have a real deadlock? That tends to be more common when using
 threads. Merely blocking (waiting for a network connection for example) is
 cleanly solvable with non-blocking IO.

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Ticket URL: <https://dev.laptop.org/ticket/2654#comment:5>
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