Hi all,
Following our previous posts (
http://lists.ros.org/lurker/message/20140918.011916.e0e9cd9e.en.html and
http://lists.ros.org/lurker/message/20140929.022230.7c75e176.en.html) , again we are posting some updates here in a separate thread.
We did some tests to demonstrate the effectiveness of the PREEMPT_RT patched Linux kernel, compared with the vanilla kernel coming with Ubuntu. To be more specific, jitters in ROS message communications (both topic- and service-based) upon the non-real-time and real-time kernels are recorded, while the source code of the test tries to maintain a fixed communication rate (10kHz in our case). The source code can be downloaded from:
http://micros.nudt.edu.cn/ros/attachments/download/6440/ros_rt_test_src.tar.gz
And the results are shown in the charts below:
http://micros.nudt.edu.cn/ros/attachments/download/6435/topic_one_subscriber.pnghttp://micros.nudt.edu.cn/ros/attachments/download/6436/topic_two_subscriber.pnghttp://micros.nudt.edu.cn/ros/attachments/download/6437/topic_four_subscriber.pnghttp://micros.nudt.edu.cn/ros/attachments/download/6438/topic_eight_subscriber.pnghttp://micros.nudt.edu.cn/ros/attachments/download/6439/service.png
The test environment is described below:OS: Ubuntu 12.04 32-bitVanilla kernel version: 3.8.0Real-time kernel version: linux-3.8.13-rt16ROS version: Groovy
Best regards,Yanzhen
_______________________________________________
ros-users mailing list
ros-users@lists.ros.org
http://lists.ros.org/mailman/listinfo/ros-users