Comment 23 for bug 1070760

Revision history for this message
In , marmuta (marmuta) wrote :

Created attachment 69773
cairo-perf results for Onboard starting up with Ambiance theme

I'm investigating why Onboard with the default theme takes upwards of 30s to start up on a Nexus 7 with Ubuntu 12.10. It's barely usable even with the simplest themes, where just a plain filled and stroked rectangle is drawn per key.

A cairo-perf-trace of Onboard starting up shows the Nexus 7 to be ~200x slower than a Sandy Bridge i3 laptop, but single-threaded CPU performance differs just by a factor of roughly 4.5 (see Attachment). Also the cairo image backends are vastly faster than the xcb/xlib one's, which is the reverse of the i3's results.

The Nexus 7 has a quad-core Tegra 3, me thinks the hardware isn't necessarily the limiting factor. Is this a driver issue? Xorg takes close to 100% CPU during heavy cairo rendering with (python-based) Onboard.

Here's the original bug report:
https://bugs.launchpad.net/ubuntu-nexus7/+bug/1070760

gtkperf on the Nexus 7:
GtkPerf 0.40 - Starting testing: Thu Nov 8 18:58:56 2012

GtkEntry - time: 0.77
GtkComboBox - time: 17.09
GtkComboBoxEntry - time: 6.95
GtkSpinButton - time: 2.42
GtkProgressBar - time: 2.91
GtkToggleButton - time: 7.59
GtkCheckButton - time: 2.12
GtkRadioButton - time: 3.66
GtkTextView - Add text - time: 6.94
GtkTextView - Scroll - time: 1.13
GtkDrawingArea - Lines - time: 12.66
GtkDrawingArea - Circles - time: 27.67
GtkDrawingArea - Text - time: 19.19
GtkDrawingArea - Pixbufs - time: 2.31
 ---
Total time: 113.47

libcairo2 1.12.2-1ubuntu2
nvidia-tegra3 binary Xorg driver 16.0-0ubuntu3