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[Dmitry Shachnev <mitya57@xxxxxxxxx>]

This is not an bug in qtchooser.

** Package changed: qtchooser (Ubuntu) => qtdeclarative-opensource-src
(Ubuntu)

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https://bugs.launchpad.net/bugs/1210124

Title:
  qmlscene is busy and there is heap growth when running idle apps

Status in qtdeclarative-opensource-src package in Ubuntu:
  New

Bug description:
  I've been using health-check from my PPA (ppa:colin-king/white) to
  observe idle states of various phone apps and I'm seeing poll/epoll
  spinning at ~10 polls a second and some heap growth even when idle.

  1. polling on idle consumes power, although small, it will accumulate when a user has multiple idle apps running
  2. the heap growth is slow but will add up if an app is running for many hours.

   Attached is the system activity on two idle apps:

  1. /usr/lib/arm-linux-gnueabihf/qt5/bin/qmlscene /usr/share/ubuntu-
  filemanager-app/ubuntu-filemanager-app

  2.  /usr/lib/arm-linux-gnueabihf/qt5/bin/qmlscene /usr/share/ubuntu-
  calculator-app/ubuntu-calculator-app

  I'm observing:

  Top polling system calls:
    PID  Process              Syscall             Rate/Sec   Infinite   Zero     Minimum    Maximum    Average
                                                             Timeouts Timeouts   Timeout    Timeout    Timeout
    2666 qmlscene             poll                    5.6278        0        4   0.0 sec    3.0 sec    1.7 sec 
    2674 qmlscene             epoll_wait              4.9650        0        0   5.0 sec    5.0 sec    5.0 sec 
    2686 qmlscene             epoll_wait              0.2000        0        0   5.0 sec    5.0 sec    5.0 sec 
   Total                                             10.7928        0        4

  so ~10Hz of polling.

  Also, heap growth:

  Change in memory (K/second):
    PID  Process              Type        Size       RSS       PSS
    2666 qmlscene             Heap        0.00      0.39      0.39 (growing slowly)

  Since the RSS + PSS are growing I guess this is an anonymous mem-
  mapped region that is slowly filling up and populating physical pages
  and at sometime we may run out and the underying user space memory
  allocator will map a larger region for more heap. But as it is, it
  seems that the physical pages are slowly getting used which generally
  points to a slow leak somewhere.  I suggest running valgrind on
  qmlscene to see if it can spot any heap leakages.

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