Bug 63597 - weston terminal: very high cpu usage
Summary: weston terminal: very high cpu usage
Status: RESOLVED NOTABUG
Alias: None
Product: Wayland
Classification: Unclassified
Component: weston (show other bugs)
Version: 1.0.90
Hardware: Other All
: medium normal
Assignee: Wayland bug list
QA Contact:
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2013-04-16 11:23 UTC by wbrana
Modified: 2013-07-08 11:45 UTC (History)
0 users

See Also:
i915 platform:
i915 features:

Attachments

Description wbrana 2013-04-16 11:23:15 UTC 
running command: top -d 0.1
causes 40% CPU usage by weston-terminal 1.1

running same command in rxvt-unicode with xorg-server causes total CPU usage by rxvt-unicode and xorg-server about 0.5%

GPU Intel Sandy Bridge GT1
Mesa 9.1.1

rxvt-unicode was tested with default bitmap font
XFCE without compositing
xf86-video-intel 2.21.6 with SNA
Comment 1 wbrana 2013-04-16 11:47:11 UTC 
terminal windows were maximized
Comment 2 Rob Bradford 2013-07-08 11:45:05 UTC 
Using sysprof to analyse this I see that we spend a large amount of time in idle_redraw - a function that is throttled by the compositor (to vblank in the DRM case and in the case of X11 every 10ms)

What we end up doing in that function is drawing all the glyphs using the Cairo image backend something that cannot really be compared with rxvt. weston-terminal is a "toy" terminal emulator and I don't believe there is any bug present here.

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.