gr-fosphor¶

GNU Radio block for RTSA-like spectrum visualization using OpenCL and OpenGL acceleration.

https://gitea.osmocom.org/sdr/gr-fosphor.git

The block has been used successfully on Linux, OSX and Windows.

Building¶

Warning: Mixed prefix install is not supported. You need to install gr-fosphor in the same prefix as your GNU Radio install. If you used build-gnuradio this will be /usr/local and this is what's used in the instructions below. If you use a packaged version of GNU Radio, it's most likely /usr and the best way is then to make a package for gr-fosphor for your distribution.

OS specific notes¶

- For OSX you probably just want to use the gr-fosphor port in macports
- For Windows you can't use the Visual C++ compiler due to some C99 constructs used in the code that it doesn't support (I mean, it's only been 15 years, you can't expect microsoft to support that bleeding edge stuff). You can use ICC or compile the C part manually using clang. It has been done, so it's possible albeit not trivial.

GLFW3¶

Install dependencies

sudo apt-get install cmake xorg-dev libglu1-mesa-dev

Build GLFW

git clone https://github.com/glfw/glfw
cd glfw
mkdir build
cd build
cmake ../ -DBUILD_SHARED_LIBS=true
make
sudo make install
sudo ldconfig

OpenCL¶

To run fosphor, you need an OpenCL implementation. This can be either a GPU implementation (which will often be the faster option), or a CPU implementation. If available, fosphor will also make use of the CL/GL sharing extension allowing to transfer data efficiently between the OpenCL compute kernels and the OpenGL rendering.

All the implementations listed below have been successfully used with fosphor.

NVidia OpenCL¶

The NVidia implementation is provided by the binary drivers and support CL/GL sharing very well. Unfortunately the 'nouveau' open-source drivers don't provide OpenCL yet.

• install NVidia drivers

sudo apt-get install nvidia-opencl-dev opencl-headers

For modern version of the distribution / drivers, you might also need :

sudo apt-get install nvidia-modprobe

AMD GPU OpenCL¶

• install AMD drivers (13.4, 13.11 beta6, 13.12, 14.10 and 14.12 drivers are known to work on linux)
• install AMD APP SDK

Intel GPU OpenCL¶

• fosphor has been confirmed to work with Iris graphics on OSX.
• It also has been used on linux using the beignet opencl
  • It doesn't support CL/GL sharing though, even if you're using the Intel GPU for display
  • Performance was disappointing on linux though, there seem to be an unidentified bottleneck.

Intel CPU OpenCL¶

Intel offers a CPU OpenCL implementation. You need a CPU capable of at least SSE 4.2 to be able to use it. This implementation has been confirmed working with fosphor and is the highest performance of all the CPU OpenCL implementation.

See this page

Installation instructions¶

Download the latest OpenCL runtime from intel.com.

In November 2015 it was opencl_runtime_14.2_x64_4.5.0.8.tgz.

That archive contains a rpm subdirectory with several .rpm files.

Extract the content of the following files, e.g. by first converting them to a .tgz with alien(1) to be able to then use tar(1).

Then selectively install parts of the content of those archives in your system.

$ mkdir $HOME/tmp
$ cd $HOME/tmp
$ wget http://registrationcenter.intel.com/irc_nas/4181/opencl_runtime_14.2_x64_4.5.0.8.tgz
$ tar xf opencl_runtime_14.2_x64_4.5.0.8.tgz
$ cd pset_opencl_runtime_14.1_x64_4.5.0.8/rpm
$ alien --to-tgz opencl-1.2-base-pset-4.5.0.8-1.noarch.rpm
$ tar xf opencl-1.2-base-4.5.0.8.tgz
$ sudo mv /opt/intel /opt
$ rm -rf opt
$ alien --to-tgz opencl-1.2-intel-cpu-4.5.0.8-1.x86_64.rpm
$ tar xf opencl-1.2-intel-cpu-4.5.0.8.tgz
$ sudo mkdir -p /etc/OpenCL/vendors
$ sudo mv opt/intel/opencl-1.2-4.5.0.8/etc/intel64.icd /etc/OpenCL/vendors/
$ sudo mv opt/intel/opencl-1.2-4.5.0.8/lib64/* /opt/intel/opencl-1.2-4.5.0.8/lib64/
$ rm -rf opt

AMD CPU OpenCL¶

AMD also has a CPU OpenCL implementation see this page for details. It's not quite as fast as the Intel one, but it doesn't require SSE 4.2 which allows it to be used on older processors.

pocl¶

"This is a free-software OpenCL CPU implementation. It's not where as performant as the Intel/AMD ones, but it's opensource and supported on any platform.

Note that at the time of writing, you need the git version to use fosphor with it due to a very recently fixed memory leak that fosphor triggers.

FreeOCL¶

[http://code.google.com/p/freeocl/":http://portablecl.org/]

This is another free-software OpenCL CPU implementation that's also been verified to work with fosphor. It uses whatever C++ compiler is installed on the system as the code generation backend.

Again, at the time of writing, you need the latest SVN version to use fosphor with it due to some recently fixed bugs that fosphor triggers.

gr-fosphor¶

Build gr-fosphor

Build dependencies: gnuradio-dev, opencl-headers, libboost-system-dev, libboost-thread-dev.

git clone https://gitea.osmocom.org/sdr/gr-fosphor.git
cd gr-fosphor
mkdir build
cd build
cmake ..
make
sudo make install
sudo ldconfig

Build benchmark tool

Build dependencies: libglfw3-dev.

cd gr-fosphor/lib/fosphor
make LDFLAGS=-L/opt/intel/opencl-1.2-4.5.0.8/lib64

Fosphor is known to build successfully on Linux, OSX and Windows.

Known issues¶

• Some version of ubuntu (like 13.10) have screwed up OpenCL dev files setup and it might be required to manually specify a path to the actual OpenCL library during the cmake step ( like -DOPENCL_LIBRARY=/usr/lib/nvidia-304/libOpenCL.so)
• When running python flowgraphs on machines with AMD graphics (fglrx driver) and UHD enabled in gr-osmosdr you may experience the following error [!] CL Error (-1001, fosphor/cl.c:268): Unable to fetch platform IDs. This is due to TLS sections in both, AMD OpenCL library and UHD library interfering with each other. A workaround is available through preloading the AMD OpenCL library LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libamdocl64.so osmocom_fft -F (path may vary). C++ flowgraphs are not affected.

Screenshots¶

Short video examples¶

http://www.youtube.com/watch?v=mjD-l3GAghU

<iframe width="960" height="720" src="http://www.youtube.com/embed/mjD-l3GAghU" frameborder="0" allowfullscreen></iframe>

osmocom_fft in fosphor mode¶

Those are when enabling the integrated 'fosphor' mode of osmocom_fft through the -F command line option

Bandwidth figures¶

There's a benchmark program available which allows to estimate the maximal bandwidth that can be processed with a specific GPU.

To build it:

cd gr-fosphor/lib/fosphor
make

Then execute it by providing a prerecorded complex float file (a couple of 100MB should be fine) in gnuradio format.

./main some.cfile

Try to leave the window to its default size if possible and watch out for the Msps numbers printed out to the console.

Submit your numbers & help us to create a GPU survey. We are especially interested in the top end and mobile graphics figures.

CPU	GPU	Msps	Notes
?	AMD R290	WANTED
?	NVidia Titan	WANTED
i7-4770K 3.5 GHz	NVidia GeForce GTX 760	~228
?	AMD Radeon HD 7970 (Tahiti)	~220
i5-3570K 3.4 GHz	AMD Radeon HD 7870 (Tahiti)	~220
i7-3770K 3.4 GHz	Nvidia GTX 660	~202
i7-3770K 3.4 Ghz	Nvidia GTX 760	~191
i7-4770K 3.5 GHz	Nvidia GTX 650 Ti Boost	~188
i5-2500 3.3 GHz	NVidia GTX 460 SE	~129
i5-3570K 3.4GHz	AMD Radeon HD 7870 (Pitcairn)	~112
i5-2500 3.3GHz	NVidia GTX 550 Ti	~110
i5-2500k 3.8GHz	AMD Radeon HD 6850	~100
?	NVidia GTX 550 Ti	~97
QC Xeon 2 GHz	Nvidia GeForce 560 Ti	~73
C2D 2.66 GHz	NVidia GeForce GT 640 (GK107)	~67
i5 2.4 GHz	Intel Iris Pro 5100	~65
i7-3610QM	NVidia GeForce GT 640M LE	~63
i7-950 3.06 GHz	NVidia GT9800	~61
i5-2500K 4.2 GHz	AMD Radeon HD 6570	~58
C2D 3.00GHz	NVidia GeForce 9800 GT	~47
i5-2520M 2.5 GHz	NVidia GF119M	~46
i3-4005U 1.70GHz	NVIDIA GeForce 840M	~62	with CL/GL sharing
i3-4005U 1.70GHz	NVIDIA GeForce 840M	~46	no CL/GL sharing
C2D 2.4GHz	NVidia 9600M GT	~31
i5-3320M	Intel CPU OpenCL	~24
?	NVidia GT330M	~22
?	NVidia 8600GT	~15
C2D 2.2GHz	NVidia NVS 140M	~14
AMD E350 Fusion APU	AMD Radeon 6310	~12
C2Q Q9650 3.00GHz	!GeForce 9300 GE	~11
Atom 330	NVidia ION	~10