Minimizing voxl-camera-server CPU usage in SDK1.6
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@Rowan-Dempster , sounds good, let me know how the testing goes.
Alex
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@Alex-Kushleyev Actually had some time today to do the profiling and explore the ION pipes.
I see the same improvements that you quoted:
On 2.2.17
Normal pipes: 45%
MISP pipes: 66%
MISP pipes + 4x tracking pipes: 160%On perf improvements
Normal pipes: 45%
MISP pipes: 52%
MISP pipes + 4x tracking pipes: 71%On perf improvements + ION pipes
MISP pipes: 48%
MISP pipes + 4x tracking pipes: 52%I started looking into using the ION pipe in the QVIO server code but saw this in the voxl-mpa-tools build script:
qrb5165) check_docker "4.3" mkdir -p build32 cd build32 cmake -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_QRB5165_1_32} \ -DBUILD_TOOLS=OFF \ -DEN_ION_BUF=OFF ../ make -j$(nproc) cd ../ mkdir -p build64 cd build64 cmake -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_QRB5165_1_64} \ -DBUILD_TOOLS=ON \ -DEN_ION_BUF=ON ../ make -j$(nproc) cd ../ ;; qrb5165-2) check_docker "4.3" mkdir -p build cd build cmake -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_QRB5165_2_64} \ -DBUILD_TOOLS=ON \ -DEN_ION_BUF=OFF ../ make -j$(nproc) cd ../ ;;Since we're using the qrb5165 (not the qrb5165-2) we have to use the 32bit toolchain to build QVIO (right?):
qrb5165) check_docker "4.4" mkdir -p build cd build cmake -DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_QRB5165_1_32} ../ make -j$(nproc) cd ../ ;;Does this mean that on the qrb5165 (using the 32 bit toolchain), the QVIO server cannot be a client to the ION pipes?
Thank you,
Rowan -
Yes, QVIO only runs as a 32-bit app due to the nature of the library from Qualcomm.
I tried to build the
voxl-image-repubapplication for 32 bit and got the following error:/usr/bin/arm-linux-gnueabi-ld: CMakeFiles/voxl-image-repub.dir/voxl-image-repub.cpp.o: in function `main': voxl-image-repub.cpp:(.text.startup+0x228): undefined reference to `pipe_client_set_ion_buf_helper_cb'So it seems like the 32-bit version of libmodal-pipe does not support sending ION buffers.
I just checked with the team - even though we have not tested the ION buffer sharing in 32-bit environment, it should work. You could try to build
libmodal-pipelibrary and enable ION support : https://gitlab.com/voxl-public/voxl-sdk/core-libs/libmodal-pipe/-/blob/master/build.sh?ref_type=heads#L76 .Then you would need to install that new library into your docker container where you are building your app, as well as deploy to VOXL2.
BTW in order to build the tools in
voxl-mpa-toolsi needed to disable-Werrorand comment out a few targets likevoxl-convert-imageandvoxl-inspect-cam-asciidue to lack of 32-bit version of opencv.So.. if you really wanted the QVIO app to use the shared ION buffers, you would have to go that route..
Alex
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@Alex-Kushleyev Hi Alex I'm running into compilation errors when building libmodal-pipe after turning the EN_ION_BUF flag ON (builds fine with the flag OFF)
Found voxl-cross version: 4.4 -- --------------------------------------------------------- -- Using voxl-cross 32-bit toolchain for QRB5165 -- C Compiler : /usr/bin/arm-linux-gnueabi-gcc-7 -- C++ Compiler : /usr/bin/arm-linux-gnueabi-g++-7 -- Sysroot : /opt/sysroots/qrb5165_1 -- C flags : -isystem=/usr/arm-linux-gnueabi/include -isystem=/usr/include -idirafter /usr/include -fno-stack-protector -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv4 -- CXX flags : -isystem=/usr/arm-linux-gnueabi/include -isystem=/usr/include -idirafter /usr/include -fno-stack-protector -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv4 -- EXE Link Flags : -L/opt/sysroots/qrb5165_1/usr/lib32 -L/opt/sysroots/qrb5165_1/lib -L/opt/sysroots/qrb5165_1/usr/lib -L/opt/sysroots/qrb5165_1/usr/arm-linux-gnueabi -L/opt/sysroots/qrb5165_1/usr/lib/gcc-cross/arm-linux-gnueabi/7 -L/usr/lib -- SO Link Flags : -L/opt/sysroots/qrb5165_1/usr/lib32 -L/opt/sysroots/qrb5165_1/lib -L/opt/sysroots/qrb5165_1/usr/lib -L/opt/sysroots/qrb5165_1/usr/arm-linux-gnueabi -L/opt/sysroots/qrb5165_1/usr/lib/gcc-cross/arm-linux-gnueabi/7 /opt/sysroots/qrb5165_1/usr/lib/gcc-cross/arm-linux-gnueabi/7/libgcc.a /opt/sysroots/qrb5165_1/usr/lib/gcc-cross/arm-linux-gnueabi/7/libgcc_eh.a /opt/sysroots/qrb5165_1/usr/lib/gcc-cross/arm-linux-gnueabi/7/libssp_nonshared.a /opt/sysroots/qrb5165_1/usr/arm-linux-gnueabi/lib/libc_nonshared.a -L/usr/lib -- The C compiler identification is GNU 7.3.0 -- The CXX compiler identification is GNU 7.3.0 -- Detecting C compiler ABI info -- Detecting C compiler ABI info - done -- Check for working C compiler: /usr/bin/arm-linux-gnueabi-gcc-7 - skipped -- Detecting C compile features -- Detecting C compile features - done -- Detecting CXX compiler ABI info -- Detecting CXX compiler ABI info - done -- Check for working CXX compiler: /usr/bin/arm-linux-gnueabi-g++-7 - skipped -- Detecting CXX compile features -- Detecting CXX compile features - done -- INFO: building with ion buf support -- INFO: building with mavlink support INFO: Skipping Building Python Bindings -- INFO: Skipping examples and tools -- Configuring done (1.8s) -- Generating done (0.0s) -- Build files have been written to: /home/root/build32 [ 10%] Building C object library/CMakeFiles/modal_pipe.dir/src/start_stop.c.o [ 30%] Building C object library/CMakeFiles/modal_pipe.dir/src/client.c.o [ 30%] Building CXX object library/CMakeFiles/modal_pipe.dir/src/buffers.cpp.o [ 50%] Building C object library/CMakeFiles/modal_pipe.dir/src/interfaces.c.o [ 50%] Building C object library/CMakeFiles/modal_pipe.dir/src/sink.c.o [ 60%] Building C object library/CMakeFiles/modal_pipe.dir/src/common.c.o [ 70%] Building C object library/CMakeFiles/modal_pipe.dir/src/misc.c.o [ 80%] Building C object library/CMakeFiles/modal_pipe.dir/src/server.c.o [ 90%] Building CXX object library/CMakeFiles/modal_pipe.dir/src/buffers/gbm.cpp.o /home/root/library/src/server.c: In function 'pipe_server_write_ion_buffer': /home/root/library/src/server.c:1757:102: error: format '%ld' expects argument of type 'long int', but argument 5 has type 'int64_t {aka long long int}' [-Werror=format=] printf("server preparing to send ion buffer id %d (fd %d) to clients, n_clients: %d, time: %ld\n", ~~^ %lld ion_buf->buffer_id, fd, c[ch].n_clients, _time_monotonic_ns()); ~~~~~~~~~~~~~~~~~~~~ /home/root/library/src/client.c: In function '_stop_helper_and_remove_pipe': /home/root/library/src/client.c:1353:56: error: format '%ld' expects argument of type 'long int', but argument 3 has type 'int64_t {aka long long int}' [-Werror=format=] if(en_debug) printf("ch: %d, shutdown socket %ld ns\n", ch, _time_monotonic_ns()); ~~^ ~~~~~~~~~~~~~~~~~~~~ %lld /home/root/library/src/client.c: In function 'pipe_client_close': /home/root/library/src/client.c:1475:43: error: format '%ld' expects argument of type 'long int', but argument 3 has type 'int64_t {aka long long int}' [-Werror=format=] printf("ch: %d, shutdown socket %ld ms\n", ch, _time_monotonic_ns()); ~~^ ~~~~~~~~~~~~~~~~~~~~ %lld cc1: all warnings being treated as errors make[2]: *** [library/CMakeFiles/modal_pipe.dir/build.make:93: library/CMakeFiles/modal_pipe.dir/src/client.c.o] Error 1 make[2]: *** Waiting for unfinished jobs.... cc1: all warnings being treated as errors make[2]: *** [library/CMakeFiles/modal_pipe.dir/build.make:149: library/CMakeFiles/modal_pipe.dir/src/server.c.o] Error 1 make[1]: *** [CMakeFiles/Makefile2:106: library/CMakeFiles/modal_pipe.dir/all] Error 2 make: *** [Makefile:136: all] Error 2Seems like I'm going down an uncharted path here. I'm okay with spending my time charting it out since getting QVIO to work with ION pipes will save us critical CPU util. Does ModalAI have plans to switch the official SDK QVIO server release (for qrb5165) to using ION pipes (I saw ModalAI switched to using the MISP pipes for QVIO a few months ago, taking a CPU hit)?
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@Rowan-Dempster, the errors above seem like print formatting issues, but i understand that there could be some others. If you want to try to resolve those and see if there are any more significant errors, I can help.
We do not plan to update QVIO to use ion pipes, mainly because QVIO only supports a single camera input, so the savings from going to ION buffers for a single camera is going to be very small. The majority of savings came from the buffer caching policy, which I pointed out in the previous email. Another reason is that we are now focusing on Open Vins, which does support multiple cameras.
We do plan to fix the buffer caching policy so to remove this extra cpu usage for the appropriate MISP outputs. The work is ongoing in the branch i mentioned above.
Are you running multiple instances of QVIO, one for each camera?
Alex
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@Alex-Kushleyev Sounds good, I proceeded with resolving the basic typing issues related to 32 bit monotonic time. Next issue is a linker error that looks a bit more tricky:
-- Build files have been written to: /home/root/build32 [ 10%] Building CXX object library/CMakeFiles/modal_pipe.dir/src/buffers.cpp.o [ 40%] Building C object library/CMakeFiles/modal_pipe.dir/src/server.c.o [ 40%] Building C object library/CMakeFiles/modal_pipe.dir/src/common.c.o [ 40%] Building C object library/CMakeFiles/modal_pipe.dir/src/misc.c.o [ 50%] Building CXX object library/CMakeFiles/modal_pipe.dir/src/buffers/gbm.cpp.o [ 60%] Building C object library/CMakeFiles/modal_pipe.dir/src/interfaces.c.o [ 70%] Building C object library/CMakeFiles/modal_pipe.dir/src/client.c.o [ 80%] Building C object library/CMakeFiles/modal_pipe.dir/src/sink.c.o [ 90%] Building C object library/CMakeFiles/modal_pipe.dir/src/start_stop.c.o [100%] Linking CXX shared library libmodal_pipe.so /opt/sysroots/qrb5165_1/usr/lib/libgbm.so: file not recognized: file format not recognized collect2: error: ld returned 1 exit status make[2]: *** [library/CMakeFiles/modal_pipe.dir/build.make:228: library/libmodal_pipe.so] Error 1 make[1]: *** [CMakeFiles/Makefile2:106: library/CMakeFiles/modal_pipe.dir/all] Error 2 make: *** [Makefile:136: all] Error 2 -
@Rowan-Dempster , yeah that is going to be a problem.. I don't think we have a 32 bit version of
libgbm.sofor VOXL2. This library is used for allocating the ION buffers.The next thing to try would be to remove the buffer allocation part from the 32-bit build. Actually receiving and reading the buffer does not involve libgbm. the client just gets a FD, which needs to be mmap'ed and used. (this would remove ability to allocate new ION buffers, which you actually don't need on the client side).
I just commented out the following from the library CMakeLists:
#list(APPEND LIBS_TO_LINK gbm) #list(APPEND all_src_files src/buffers/gbm.cpp)and here are the errors:
/usr/bin/aarch64-linux-gnu-ld: CMakeFiles/modal_pipe.dir/src/buffers.cpp.o: in function `mpa_ion_buf_pool_alloc_bufs': buffers.cpp:(.text+0x10c): undefined reference to `allocate_one_buffer(mpa_ion_buf_t*, int, int, unsigned int, unsigned int)' /usr/bin/aarch64-linux-gnu-ld: buffers.cpp:(.text+0x184): undefined reference to `init_buffer_allocator()' /usr/bin/aarch64-linux-gnu-ld: CMakeFiles/modal_pipe.dir/src/buffers.cpp.o: in function `mpa_ion_buf_pool_delete_bufs': buffers.cpp:(.text+0x24c): undefined reference to `delete_one_buffer(mpa_ion_buf_t*)' /usr/bin/aarch64-linux-gnu-ld: buffers.cpp:(.text+0x2a0): undefined reference to `shutdown_buffer_allocator()'You could try replacing those functions with a fatal print statement "not implemented". Maybe that would work?
Alex
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@Alex-Kushleyev Hi Alex, I compiled libmodal-pipe with ION client-only support in 32 bit builds. I then changed the voxl-mpa-tools toolchain to 32 bit and set the 32 bit toolchain to actually build the tool executables and removed the ones that didn't compile. After deploying those two modified packages to the VOXL2 and running the same repub command that I ran before, I am getting a runtime error while parsing the incoming ION buffers on the client side
voxl2:/$ voxl-image-repub top_misp_norm_ion -o top_misp_norm_ion_test Subscribed to ION input pipe: top_misp_norm_ion invalid metadata, magic number=85, expected 1229934146 invalid metadata, magic number=85, expected 1229934146 invalid metadata, magic number=85, expected 1229934146Tracking it down, it looks like the call to
pipe_client_bytes_in_pipein the_ion_buf_cbis what's printing the error. If I remove that line (so not returning ifpipe_client_bytes_in_pipereturns0) it prints some garbage (incorrect) metadata and then segfaults:voxl2:/$ voxl-image-repub top_misp_norm_ion -o top_misp_norm_ion_test Subscribed to ION input pipe: top_misp_norm_ion CH0 Got input ion frame size: 10330x-2843, format: STEREO_NV12, stride: 50834, size: 396 bytes Segmentation fault: Fault thread: voxl-image-repu(tid: 7900) Fault address: 0x4 Address not mapped. Segmentation faultNote that I didn't recompile voxl-camera-server on-top of the modified libmodal-pipe, don't think that would change anything.
Let me know if you want me to send you my diffs of libmodal-pipe (w.r.t.
master) and voxl-mpa-tools (w.r.t.add-new-image-tools).P.S. I also tried
voxl-inspect-ion-stream top_misp_norm_ion(that tool is also 32 bit now) and it's printing garbage too| Pipe Name | fd | bytes | wide | hgt |exp(ms)| gain | frame id |latency(ms)| fps | mbps |t | top_misp_norm_ion | 6 | 455 | 3237 |-29847 | 52.43 |-24576 |1448040524 |1955547.7 | 30.0 | 0.6 -
I think you are close.. sure, if you want to share the diff or make a fork of the repos, I will try it out.
Alex
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@Alex-Kushleyev Here are the diffs:
- libmodal-pipe: https://gitlab.com/rowan.dempster/libmodal-pipe/-/merge_requests/1/diffs
- voxl-mpa-tools: https://gitlab.com/rowan.dempster/voxl-mpa-tools/-/merge_requests/1/diffs
Thanks for your help!
