4 **apitrace** consists of a set of tools to:
6 * trace OpenGL, OpenGL ES, Direct3D, and DirectDraw APIs calls to a file;
8 * retrace OpenGL and OpenGL ES calls from a file;
10 * inspect OpenGL state at any call while retracing;
12 * visualize and edit trace files.
15 Obtaining **apitrace**
16 ======================
18 To obtain apitrace either [download the latest
19 binaries](https://github.com/apitrace/apitrace/downloads) for your platform if
20 available, or follow the instructions in INSTALL.markdown to build it yourself.
21 On 64bits Linux and Windows platforms you'll need apitrace binaries that match
22 the architecture (32bits or 64bits) of the application being traced.
28 Run the application you want to trace as
30 apitrace trace --api API /path/to/application [args...]
32 and it will generate a trace named `application.trace` in the current
33 directory. You can specify the written trace filename by passing the
34 `--output` command line option.
36 Problems while tracing (e.g, if the application uses calls/parameters
37 unsupported by apitrace) will be reported via stderr output on Unices. On
38 Windows you'll need to run
39 [DebugView](http://technet.microsoft.com/en-us/sysinternals/bb896647) to view
42 Follow the "Tracing manually" instructions below if you cannot obtain a trace.
46 apitrace dump application.trace
48 Replay an OpenGL trace with
50 glretrace application.trace
52 Pass the `-sb` option to use a single buffered visual. Pass `--help` to
53 glretrace for more options.
61 qapitrace application.trace
63 You can also tell the GUI to go directly to a specific call
65 qapitrace application.trace 12345
68 Advanced command line usage
69 ===========================
75 Several tools take `CALLSET` arguments, e.g:
77 apitrace dump --calls CALLSET foo.trace
78 glretrace -S CALLSET foo.trace
80 The call syntax is very flexible. Here are a few examples:
84 * `1,2,4,5` set of calls
86 * `"1 2 4 5"` set of calls (commas are optional and can be replaced with whitespace)
88 * `1-100/2` calls 1, 3, 5, ..., 99
90 * `1-1000/draw` all draw calls between 1 and 1000
92 * `1-1000/fbo` all fbo changes between calls 1 and 1000
94 * `frame` all calls at end of frames
96 * `@foo.txt` read call numbers from `foo.txt`, using the same syntax as above
105 On 64 bits systems, you'll need to determine ether the application is 64 bits
106 or 32 bits. This can be done by doing
108 file /path/to/application
110 But beware of wrapper shell scripts -- what matters is the architecture of the
113 Run the application you want to trace as
115 LD_PRELOAD=/path/to/apitrace/wrappers/glxtrace.so /path/to/application
117 and it will generate a trace named `application.trace` in the current
118 directory. You can specify the written trace filename by setting the
119 `TRACE_FILE` environment variable before running.
121 The `LD_PRELOAD` mechanism should work with most applications. There are some
122 applications, e.g., Unigine Heaven, which global function pointers with the
123 same name as GL entrypoints, living in a shared object that wasn't linked with
124 `-Bsymbolic` flag, so relocations to those globals function pointers get
125 overwritten with the address to our wrapper library, and the application will
126 segfault when trying to write to them. For these applications it is possible
127 to trace by using `glxtrace.so` as an ordinary `libGL.so` and injecting into
130 ln -s glxtrace.so wrappers/libGL.so
131 ln -s glxtrace.so wrappers/libGL.so.1
132 ln -s glxtrace.so wrappers/libGL.so.1.2
133 export LD_LIBRARY_PATH=/path/to/apitrace/wrappers:$LD_LIBRARY_PATH
134 export TRACE_LIBGL=/path/to/real/libGL.so.1
137 See the `ld.so` man page for more information about `LD_PRELOAD` and
138 `LD_LIBRARY_PATH` environment flags.
140 To trace the application inside gdb, invoke gdb as:
142 gdb --ex 'set exec-wrapper env LD_PRELOAD=/path/to/glxtrace.so' --args /path/to/application
146 The following instructions should work at least for Android Ice Scream
149 For standalone applications the instructions above for Linux should
150 work. To trace applications started from within the Android VM process
151 (app_process aka zygote) you'll have to wrap this process and enable
152 tracing dynamically for the application to be traced.
154 - Wrapping the android main VM process:
156 In the Android root /init.rc add the LD_PRELOAD setting to zygote's
157 environment in the 'service zygote' section:
161 setenv LD_PRELOAD /data/egltrace.so
165 Note that ICS will overwrite the /init.rc during each boot with the
166 version in the recovery image. So you'll have to change the file in
167 your ICS source tree, rebuild and reflash the device.
168 Rebuilding/reflashing only the recovery image should be sufficient.
171 - Copy egltrace.so to /data
174 $ adb push /path/to/apitrace/build/wrappers/egltrace.so /data
177 - Adjust file permissions to store the trace file:
179 By default egltrace.so will store the trace in
180 /data/app_process.trace. For this to work for applications running
181 with a uid other than 0, you have to allow writes to the /data
182 directory on the device:
187 - Enable tracing for a specific process name:
189 To trace for example the Settings application:
190 # setprop debug.apitrace.procname com.android.settings
192 In general this name will match what 'ps' reports.
195 - Start the application:
197 If the application was already running, for example due to ICS's way
198 of pre-starting the apps, you might have to kill the application
203 Launch the application for example from the application menu.
207 Run the application you want to trace as
209 DYLD_LIBRARY_PATH=/path/to/apitrace/wrappers /path/to/application
211 Note that although Mac OS X has an `LD_PRELOAD` equivalent,
212 `DYLD_INSERT_LIBRARIES`, it is mostly useless because it only works with
213 `DYLD_FORCE_FLAT_NAMESPACE=1` which breaks most applications. See the `dyld` man
214 page for more details about these environment flags.
218 When tracing third-party applications, you can identify the target
219 application's main executable, either by:
221 * right clicking on the application's icon in the _Start Menu_, choose
222 _Properties_, and see the _Target_ field;
224 * or by starting the application, run Windows Task Manager (taskmgr.exe), right
225 click on the application name in the _Applications_ tab, choose _Go To Process_,
226 note the highlighted _Image Name_, and search it on `C:\Program Files` or
227 `C:\Program Files (x86)`.
229 On 64 bits Windows, you'll need to determine ether the application is a 64 bits
230 or 32 bits. 32 bits applications will have a `*32` suffix in the _Image Name_
231 column of the _Processes_ tab of _Windows Task Manager_ window.
233 Copy the appropriate `opengl32.dll`, `d3d8.dll`, or `d3d9.dll` from the
234 wrappers directory to the directory with the application you want to trace.
235 Then run the application as usual.
237 You can specify the written trace filename by setting the `TRACE_FILE`
238 environment variable before running.
241 Emitting annotations to the trace
242 ---------------------------------
244 From OpenGL applications you can embed annotations in the trace file through the
245 [`GL_GREMEDY_string_marker`](http://www.opengl.org/registry/specs/GREMEDY/string_marker.txt)
247 [`GL_GREMEDY_frame_terminator`](http://www.opengl.org/registry/specs/GREMEDY/frame_terminator.txt)
250 **apitrace** will advertise and intercept these GL extensions independently of
251 the GL implementation. So all you have to do is to use these extensions when
254 For example, if you use [GLEW](http://glew.sourceforge.net/) to dynamically
255 detect and use GL extensions, you could easily accomplish this by doing:
259 if (GLEW_GREMEDY_string_marker) {
260 glStringMarkerGREMEDY(0, __FUNCTION__ ": enter");
265 if (GLEW_GREMEDY_string_marker) {
266 glStringMarkerGREMEDY(0, __FUNCTION__ ": leave");
271 This has the added advantage of working equally well with gDEBugger.
274 From OpenGL ES applications you can embed annotations in the trace file through the
275 [`GL_EXT_debug_marker`](http://www.khronos.org/registry/gles/extensions/EXT/EXT_debug_marker.txt)
279 For Direct3D applications you can follow the same procedure used for
280 [instrumenting an application for PIX](http://technet.microsoft.com/en-us/query/ee417250)
283 Dump GL state at a particular call
284 ----------------------------------
286 You can get a dump of the bound GL state at call 12345 by doing:
288 glretrace -D 12345 application.trace > 12345.json
290 This is precisely the mechanism the GUI obtains its own state.
292 You can compare two state dumps by doing:
294 apitrace diff-state 12345.json 67890.json
297 Comparing two traces side by side
298 ---------------------------------
300 apitrace diff trace1.trace trace2.trace
302 This works only on Unices, and it will truncate the traces due to performance
306 Recording a video with FFmpeg
307 -----------------------------
309 You can make a video of the output by doing
311 glretrace -s - application.trace \
312 | ffmpeg -r 30 -f image2pipe -vcodec ppm -i pipe: -vcodec mpeg4 -y output.mp4
318 You can make a smaller trace by doing:
320 apitrace trim --callset 100-1000 -o trimed.trace applicated.trace
322 If you need precise control over which calls to trim you can specify the
323 individual call numbers a plaintext file, as described in the 'Call sets'
330 You can perform gpu and cpu profiling with the command line options:
332 * `-pgpu` record gpu times for frames and draw calls.
334 * `-pcpu` record cpu times for frames and draw calls.
336 * `-ppd` record pixels drawn for each draw call.
338 The results from this can then be read by hand or analysed with a script.
340 scripts/profileshader.py will read the profile results and format them into a
341 table which displays profiling results per shader.
343 For example, to record all profiling data and utilise the per shader script:
344 ./glretrace -pgpu -pcpu -ppd foo.trace | ./scripts/profileshader.py
347 Advanced usage for OpenGL implementors
348 ======================================
350 There are several advanced usage examples meant for OpenGL implementors.
356 These are the steps to create a regression test-suite around **apitrace**:
360 * obtain reference snapshots, by doing on a reference system:
362 mkdir /path/to/reference/snapshots/
363 glretrace -s /path/to/reference/snapshots/ application.trace
365 * prune the snapshots which are not interesting
367 * to do a regression test, do:
369 glretrace -c /path/to/reference/snapshots/ application.trace
371 Alternatively, for a HTML summary, use `apitrace diff-images`:
373 glretrace -s /path/to/test/snapshots/ application.trace
374 apitrace diff-images --output summary.html /path/to/reference/snapshots/ /path/to/test/snapshots/
377 Automated git-bisection
378 -----------------------
380 With tracecheck.py it is possible to automate git bisect and pinpoint the
381 commit responsible for a regression.
383 Below is an example of using tracecheck.py to bisect a regression in the
384 Mesa-based Intel 965 driver. But the procedure could be applied to any GL
385 driver hosted on a git repository.
387 First, create a build script, named build-script.sh, containing:
391 export PATH=/usr/lib/ccache:$PATH
394 ./autogen.sh --disable-egl --disable-gallium --disable-glut --disable-glu --disable-glw --with-dri-drivers=i965
398 It is important that builds are both robust, and efficient. Due to broken
399 dependency discovery in Mesa's makefile system, it was necessary invoke `make
400 clean` in every iteration step. `ccache` should be installed to avoid
401 recompiling unchanged source files.
406 export LIBGL_DEBUG=verbose
407 export LD_LIBRARY_PATH=$PWD/lib
408 export LIBGL_DRIVERS_DIR=$PWD/lib
410 6491e9593d5cbc5644eb02593a2f562447efdcbb 71acbb54f49089b03d3498b6f88c1681d3f649ac \
411 -- src/mesa/drivers/dri/intel src/mesa/drivers/dri/i965/
412 git bisect run /path/to/tracecheck.py \
413 --precision-threshold 8.0 \
414 --build /path/to/build-script.sh \
415 --gl-renderer '.*Mesa.*Intel.*' \
416 --retrace=/path/to/glretrace \
417 -c /path/to/reference/snapshots/ \
418 topogun-1.06-orc-84k.trace
420 The trace-check.py script will skip automatically when there are build
423 The `--gl-renderer` option will also cause a commit to be skipped if the
424 `GL_RENDERER` is unexpected (e.g., when a software renderer or another GL
425 driver is unintentionally loaded due to missing symbol in the DRI driver, or
426 another runtime fault).
429 Side by side retracing
430 ----------------------
432 In order to determine which draw call a regression first manifests one could
433 generate snapshots for every draw call, using the `-S` option. That is, however,
434 very inefficient for big traces with many draw calls.
436 A faster approach is to run both the bad and a good GL driver side-by-side.
437 The latter can be either a previously known good build of the GL driver, or a
438 reference software renderer.
440 This can be achieved with retracediff.py script, which invokes glretrace with
441 different environments, allowing to choose the desired GL driver by
442 manipulating variables such as `LD_LIBRARY_PATH`, `LIBGL_DRIVERS_DIR`, or
445 For example, on Linux:
447 ./scripts/retracediff.py \
448 --ref-env LD_LIBRARY_PATH=/path/to/reference/GL/implementation \
449 --retrace /path/to/glretrace \
450 --diff-prefix=/path/to/output/diffs \
455 python scripts\retracediff.py --retrace \path\to\glretrace.exe --ref-env TRACE_LIBGL=\path\to\reference\opengl32.dll application.trace
463 * [Official mailing list](http://lists.freedesktop.org/mailman/listinfo/apitrace)
465 * [Zack Rusin's blog introducing the GUI](http://zrusin.blogspot.com/2011/04/apitrace.html)
467 * [Jose's Fonseca blog introducing the tool](http://jrfonseca.blogspot.com/2008/07/tracing-d3d-applications.html)
475 * [Proxy DLL](http://www.mikoweb.eu/index.php?node=21)
477 * [Intercept Calls to DirectX with a Proxy DLL](http://www.codeguru.com/cpp/g-m/directx/directx8/article.php/c11453/)
479 * [Direct3D 9 API Interceptor](http://graphics.stanford.edu/~mdfisher/D3D9Interceptor.html)
483 * [Microsoft PIX](http://msdn.microsoft.com/en-us/library/ee417062.aspx)
485 * [D3DSpy](http://doc.51windows.net/Directx9_SDK/?url=/directx9_sdk/graphics/programmingguide/TutorialsAndSamplesAndToolsAndTips/Tools/D3DSpy.htm): the predecessor of PIX
487 * [NVIDIA PerfKit](http://developer.nvidia.com/nvidia-perfkit)
489 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)
491 * [Intel Graphics Performance Analyzers](http://www.intel.com/software/gpa/)
499 * [BuGLe](http://www.opengl.org/sdk/tools/BuGLe/)
501 * [GLIntercept](http://code.google.com/p/glintercept/)
503 * [tracy](https://gitorious.org/tracy): OpenGL ES and OpenVG trace, retrace, and state inspection
505 * [WebGL-Inspector](http://benvanik.github.com/WebGL-Inspector/)
509 * [gDEBugger](http://www.gremedy.com/products.php) and [AMD gDEBugger](http://developer.amd.com/tools/gDEBugger/Pages/default.aspx)
511 * [glslDevil](http://cumbia.informatik.uni-stuttgart.de/glsldevil/index.html)
513 * [AMD GPU PerfStudio](http://developer.amd.com/gpu/PerfStudio/pages/APITraceWindow.aspx)