How to monitor the display framerate

Stable: 16.01.2020 - 15:11 / Revision: 16.01.2020 - 15:07

I am here to prevent the first-page-empty bug!

When an animation is running on the display, the related framerate can be monitored from the display driver level thanks to the command:

 (while true; do export fps=`cat /sys/kernel/debug/dri/0/state | grep fps -m1 | grep -o '[0-9]\+'`; echo display ${fps}fps; sleep 4; done) &

The display framerate is then periodically output in the user console in "fps" (frames per second):

display 50fps
display 50fps
display 50fps

Notes:

  • Stop monitoring the framerate with the command "kill -9 `ps -o ppid= -C sleep`".
  • Adjust the framerate update period by modifying the "sleep" value (4 seconds in the example).
  • Use the command "dmesg -n8" to mix both user and kernel console outputs.
  • Debugfs configuration needs to be enabled.


IMPORTANT NOTICE – READ CAREFULLY
STMicroelectronics NV and its subsidiaries ("ST") reserve the right to make changes, corrections, enhancements, modifications, and improvements to ST products and/or to this document at any time without notice. Purchasers should obtain the latest relevant information on ST products before placing orders. ST products are sold pursuant to ST’s terms and conditions of sale in place at the time of order acknowledgment.

Purchasers are solely responsible for the choice, selection, and use of ST products and ST assumes no liability for application assistance or the design of purchasers’ products.

No license, express or implied, to any intellectual property right is granted by ST herein.

Resale of ST products with provisions different from the information set forth herein shall void any warranty granted by ST for such product.

ST and the ST logo are trademarks of ST. For additional information about ST trademarks, refer to www.st.com/trademarks. All other product or service names are the property of their respective owners.

Information in this document supersedes and replaces information previously supplied in any prior versions of this document.