Performance feedback [closed]

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Okay, taking a look at various benchmarks begins to help us understand what is going on with performance, and give us a better answer to a previous question about what hardware works best, question 111. For example.

http://www.tomshardware.com/reviews/core-i7-3970x-sandy-bridge-e-benchmark,3348.html

Currently, Gazebo does not distribute its load well across threads. The simulation thread acts as a single heavy load. This means that CPUs that do well on a single thread, such as the Ivy Bridge i7-3770K, work well. This pushes you towards single CPU systems that you overclock as much as possible. You don't get a benefit out of more CPUs, or more cores, as these typically cut down your effective clock rate which reduces performance on the single rate limiting simulation thread.

Let's test this hypothesis. Anybody getting real time factors out of the box on DRCSIM 1.3.1 of close to 1.0 running just

source /usr/share/drcsim/setup.sh
roslaunch atlas_utils atlas.launch

?

Anybody with i7-39xx CPUS who can give timing feedback?

It will also be interesing to see what happens to the simulation thread loading with the Bullet dynamics engine with multi-threading and use of GPUs for dynamics. This may unload the simulation thread by making it several threads or off-loading it to a GPU, and flip the performance criteria back to slower CPUs with more cores, or more slower CPUs.

In the meantime, it would be very nice if the Gazebo folks could break the simulation thread into 2 or more threads, separating the dynamics code from the ROS code with a shared memory interface. This would allow the DRCSIM software to run on a wider range of machines out of the box.

Thanks, Chris

4x Intel(R) Xeon(R) CPU 5160 @ 3.00GHz
4G memory
Nvidea GFORCE 9800 GT

DRCSIM 1.3.1 out of the box

Real Time Factor hovers around 0.55

ps augx says

cga      24022  0.3  0.4 292896 18756 pts/9    Sl+  15:45   0:01 /usr/bin/python /opt/ros/fuerte/bin/roslaunch atlas_utils atlas.launch
cga      24038  0.3  0.3 498756 12948 ?        Ssl  15:45   0:01 /usr/bin/python /opt/ros/fuerte/bin/rosmaster --core -p 11311 __log:=/home/cga/.ros/log/90863ae6-5a9d-11e2-b3e8-00188b0ade60
cga      24051  2.6  0.1 317612  6824 ?        Ssl  15:45   0:11 /opt/ros/fuerte/share/rosout/bin/rosout __name:=rosout __log:=/home/cga/.ros/log/90863ae6-5a9d-11e2-b3e8-00188b0ade60/rosout
cga      24054  0.0  0.0   4404   620 ?        Ss   15:45   0:00 /bin/sh /usr/share/drcsim-1.3/ros/atlas_utils/scripts/run_gazebo atlas.world __name:=gazebo __log:=/home/cga/.ros/log/90863a
cga      24055  0.0  0.7 360836 30264 ?        Sl   15:45   0:00 gazebo -s libgazebo_ros_api_plugin.so atlas.world
cga      24056  4.3  0.2 503988 10472 ?        Ssl  15:45   0:19 /opt/ros/fuerte/stacks/robot_model/robot_state_publisher/bin/state_publisher __name:=robot_state_publisher __log:=/home/cga/
cga      24057  3.1  0.1 393552  6836 ?        Ssl  15:45   0:13 /opt/ros/fuerte/stacks/pr2_mechanism/pr2_mechanism_diagnostics/bin/pr2_mechanism_diagnostics __name:=pr2_mechanism_diagnosti
cga      24058  0.1  0.4 358364 16380 ?        Ssl  15:45   0:00 python /opt/ros/fuerte/share/rostopic/scripts/rostopic pub /calibrated std_msgs/Bool true __name:=fake_joint_calibration __l
cga      24086  4.3  0.7 545808 31072 ?        Ssl  15:45   0:19 /opt/ros/fuerte/stacks/geometry_experimental/tf2_ros/bin/buffer_server __name:=tf2_buffer_server __log:=/home/cga/.ros/log/9
cga      24087  4.2  0.4 507916 16656 ?        Ssl  15:45   0:18 python /opt/ros/fuerte/stacks/pr2_mechanism/pr2_controller_manager/scripts/spawner --wait-for=/calibrated atlas_controller _
cga      24116  3.2  0.4 1053416 16952 ?       Ssl  15:45   0:14 /opt/ros/fuerte/stacks/image_pipeline/stereo_image_proc/bin/stereo_image_proc __name:=stereo_proc __log:=/home/cga/.ros/log/
cga      24156  174  6.1 3124276 249132 ?      Rl   15:46  12:44 gazebo -s libgazebo_ros_api_plugin.so atlas.world
cga      24157 21.7  5.1 1504336 210060 ?      Sl   15:46   1:35 gazebo -s libgazebo_ros_api_plugin.so atlas.world

In a ROS-free version of DRCSIM (all plugins removed except one Gazebo controller plugin using full state feedback (hint hint), model re-implemented in SDF 1.3)

Real Time Factor hovers around 0.95

ps augx says:

cga      25929  0.0  0.7 360836 30324 pts/1    Sl+  15:56   0:00 gazebo world
cga      25931 99.5  2.0 1036884 83340 pts/1   Sl+  15:56   2:25 gazebo world
cga      25932 24.2  4.6 1479344 189288 pts/1  Sl+  15:56   0:35 gazebo world

This was a substantial machine in its time. It got us through the Little Dog project, and we were proud of it. It can barely keep up with the ROS-free version.