Improving Cross Desktop Standard by Cedric BAIL (GNOME Asia Summit 2013)

2. Improving cross desktop standard
Cedric BailCedric Bail
<cedric@efl.so><cedric@efl.so>
<cedric.bail@samsung.com><cedric.bail@samsung.com>

3. Who am I ?
• French free software developer in Korea
• Enlightenment developer since 2005
• Work for Samsung Mobile in Korea
• On Enlightenment Foundation Libraries

4. What is this talk about ?
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Give some context about Enlightenment
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Sharing experience
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Wayland usage
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Systemd usage

5. Why ?
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Improve link across community
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All about Free software
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Sharing experience and knowledge
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Lead to a better experience for everyone

6. Why ?
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Better communication across project !
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Seriously !
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Build better and stronger base for everyone
to use
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To get better standard, people need to
understand each other goal

7. Enlightenment ?
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X Windows manager started in 1997
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Enlightenment 0.17 released 21/12/2012
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Composite manager
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Wayland server
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Wrote our own C toolkit, EFL
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And our own terminal emulator

8. 88
Enlightenment ?
< Screenshot of Enlightenment Window Manager >

9. Enlightenment ?
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Was GNOME windows manager more than
10 years ago.
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Due to a conflict between Carsten and
Miguel, each of them took their own path
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Argument was about the integration of the
windows manager with the desktop

10. Enlightenment ?
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The year of Linux Desktop will not happen
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The future will be in the embedded world
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That was in 2001 and defined where
Enlightenment community worked on.
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Goal :
– Serve us, developers
– Serve the embedded world

11. Enlightenment ?
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In fact, this two goal where the same
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Need a buttload of options
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Light on CPU and memory usage
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Easily themable
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Easily adaptable to various screen and input

12. Performance matters ?
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Embedded device don't have
– Much memory
– Much CPU
– Much GPU, if at all
– Much battery
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In fact, optimizing for battery imply
optimizing for all the other goals !

13. Memory and battery ?
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Used memory need to be always powered
●
Accessing memory use more energy than
accessing cache
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Embedded memory bandwidth don't
increase
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No swap

14. CPU and battery ?
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Obviously, the more you use it...
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What does use means with modern CPU :
– Have multiple core
– With different characteristic
– Change their clock
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Use as little as possible and make them go
back to sleep as soon as possible

15. GPU and battery ?
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Avoid fullscreen rendering
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Avoid memcpy (on the GPU to)
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No dependencies between frame
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Use hardware layer to avoid compositing
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If not, software compositor may be lighter

16. Battery ?
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Don't follow Moore's Law !
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Core i7 is as efficient as a Cortex A8 !
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Little hope into a Moore's Law for SoC power
consumption
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Battery will always be a limit

17. Battery ?
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EFL/E17 use 10% less battery than Android
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With Unity my laptop loose 1 hour of
autonomy according to powertop
●
Closing my webbrowser give me 1 more
hour of autonomy
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True on a x86 laptop to !

18. Beyond desktop !

19. Beyond desktop !

20. Beyond desktop
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1.5 Billion Android device in 2013
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More than the number of desktop in use
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Developing country jumping on Android
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No free software
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Gate to our today life !
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As powerful as some laptop !

21. Specific software ?
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An application per device ?
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Screen variation ?
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Reading distance ?
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Input ?
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Optimized for mobile ?
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Not really specific !

22. Memory optimization
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Share content across application, mmap !
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Maybe finally a sensible .desktop
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Share glyph and pixels across applications
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Need help from the kernel to decide when
to really throw those data away
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Toolkit should agree on a common cache

23. Screen variation
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DPI is not enough
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Distance to screen matter
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Personnal sighseeing to
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Scale factor for all readable elements per
screen
=> Should be a cross desktop standard and
handle by toolkit

24. Input variation
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Not everyone has the same fingers !

25. Suspending
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Throw all cached ressource away
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Interact with the system nicely on suspend
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On iconify EFL application throttle
themselves (yes, sleep in the main loop)
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Drop frame rate when minimized

26. Wayland
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X is impossible to secure by design
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Designed more than 20 years ago
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Compositing was added later on
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A lot was learned
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It is a great time to clean stuff
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Needed to be competitiv

27. Wayland
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More efficient by design
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Should be better than Android
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Should be more secure
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Some backward compatibility for X apps
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Create more work on Composite Manager
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We need to all agree on the standard

28. Wayland

29. Wayland

30. Wayland
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First always compositing
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Handle Wayland client under X
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Become a full Wayland compositor

31. Systemd
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Enlightenment_start replacement
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More reliable
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Handle monitoring of many process
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Can monitor :
– Evas_Cserve2
– Elev8d
– Elm_Quicklaunch

32. Systemd
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Could it take care of more ?
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Launching/sandboxing application
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Converting .desktop
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Multi-instance application ?
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Toolkit pre-initialization daemon ?
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Maybe not a problem necessary to solve

33. Question ?