← Back to team overview

touch-packages team mailing list archive

[Bug 1236508] Re: unity8+Mir draws more current and wakes up 100 times more often than unity8 with surfaceflinger

 

** No longer affects: unity8

-- 
You received this bug notification because you are a member of Ubuntu
Touch seeded packages, which is subscribed to unity8 in Ubuntu.
https://bugs.launchpad.net/bugs/1236508

Title:
  unity8+Mir draws more current and wakes up 100 times more often than
  unity8 with surfaceflinger

Status in Mir:
  Incomplete
Status in The Ubuntu Power Consumption Project:
  New
Status in Unity Mir:
  Incomplete
Status in “unity8” package in Ubuntu:
  Incomplete

Bug description:
  I've looked at the CPU, wakeup event and current drawn on a LG Nexus 4
  comparing the Mir enabled and non-Mir versions of Unity8 with today's
  image + updates (at 18:00 UTC, 7th Oct 2013).

  I ran a 5 minute idle soak test with the screen set to be un-blanked
  at full brightness and measured the current drawn at 0.5 second
  intervals.  The Mir enabled version of Unity is drawing on average
  ~143.7mA where as the non-Mir version is drawing 138.7mA, or around
  5mA less current (~3.6% difference)

  Measuring CPU load (just Mir)
  Mir:
    0.70% user,    0.63% system,   1.33% total CPU usage
  Non-Mir:
    0.17% user,   0.07% system,   0.23% total CPU usage

  
  Context Switches:
  Mir:
      219.24 context switches/sec
  Non-Mir:
      22.32 context switches/sec

  poll/epoll/nanosleeps 
  Mir:
     4.9664/sec
  Non-Mir:
     3.1333/sec

  
  Total CPU of system:
  Mir:
     0.87%
  Non-Mir:
     0.70%

  So it seems that the Mir variant of Unity8 is busier and consumes more
  power than the non-Mir variety when idle.

To manage notifications about this bug go to:
https://bugs.launchpad.net/mir/+bug/1236508/+subscriptions