4.7 KiB
OpenMW ships with its own benchmarking tool. This document describes how to collect performance data and vizualise it.
Collecting data
The data collected is the same as displayed by repeatedly pressing F3 and/or F4 while in the game (correspondance is shown below).
We can select what should be collected by setting the OPENMW_OSG_STATS_LIST environment variables to a semi-colon separated list of metrics to collect. There can be any combination and order doesn't matter. Note that data collection can significantly reduce performance
| Metric to collect | Equivalent in-game profiler |
|---|---|
frame_rate |
Frame rate |
engine |
OpenMW specifics metric (white bars) |
event |
Event traversal bar |
update |
Update traversal bar |
rendering |
Draw bar |
gpu |
GPU bar |
times |
Alias for event;update;rendering;engine;gpu, that is all graphs |
cameraobjects |
Table shown when pressing F3 3 times |
viewerobjects |
Table shown when pressing F3 4 times |
resource |
Table shown when pressing F4 |
It is necessary to write the collected metrics to a file which needs to be defined by the OPENMW_OSG_STATS_FILE environment variable.
Example
Posix shell
OPENMW_OSG_STATS_FILE=/tmp/stats OPENMW_OSG_STATS_LIST="resource;engine" /usr/local/bin/openmw
Windows PowerShell
$env:OPENMW_OSG_STATS_FILE="c:\stats"
$env:OPENMW_OSG_STATS_LIST="resource;engine"
openmw
Analyzing results
scripts/osg_stats.py is a python script that can perform statistical analysis and generate graphs from a trace. It doesn't need to be run on the same machine as the trace was taken.
osg_stats.py --help list the available options.
Examples
Print the available metrics in a given trace file
osg_stats.py --print_keys /tmp/stats
Sample output
gui_time_begin gui_time_end gui_time_taken input_time_begin input_time_end input_time_taken lua_time_begin lua_time_end lua_time_taken mechanics_time_begin mechanics_time_end mechanics_time_taken physics_time_begin physics_time_end physics_time_taken physicsworker_time_begin physicsworker_time_end physicsworker_time_taken script_time_begin script_time_end script_time_taken sound_time_begin sound_time_end sound_time_taken state_time_begin state_time_end state_time_taken world_time_begin world_time_end world_time_taken
Print a table with statistics data for some metrics
osg_stats.py --stats physicsworker_time_taken --stats mechanics_time_taken --stats world_time_taken --stats physics_time_taken /tmp/stats
Sample output
source key number min max mean median stdev q95 /tmp/stats physicsworker_time_taken 56245 0.0 0.01526 0.0018826463330073784 7.7e-05 0.003210274653689913 0.009509799999999995 /tmp/stats mechanics_time_taken 56245 0.0 0.015808 0.0030202102942483776 0.002177 0.002565895193458489 0.008489799999999995 /tmp/stats world_time_taken 56245 0.0 0.003643 5.230777846919726e-05 5.1e-05 1.7322475294417906e-05 6.6e-05 /tmp/stats physics_time_taken 56245 0.0 0.004407 0.00019985403146946396 0.000129 0.0002106166003676915 0.000697
Plot a timeserie of aforementioned metrics, ignoring first 1000 frames
osg_stats.py --begin_frame 1000 --end_frame 1200 --timeseries physicsworker_time_taken --timeseries mechanics_time_taken --timeseries world_time_taken --timeseries physics_time_taken /tmp/stats
Plot time spent in physics and mechanics depending on number of actors in the scene
osg_stats.py --plot 'Physics Actors' physicsworker_time_taken mean --plot 'Physics Actors' mechanics_time_taken mean --plot 'Physics Actors' physics_time_taken mean /tmp/stats
Plot timeserie from 2 traces
osg_stats.py --timeseries 'Frame Duration' /tmp/shadowson /tmp/shadowsoff