Cuda support

EACirc provides a version of gate circuit that is capable of running on CUDA devices. EACirc must be compiled with special settings to enable CUDA support. The CUDA-enabled binary can run considerably faster. To run the accelerated computation you need s special GPU supporting CUDA (basically any modern nVIDIA GPU). The minimal supported GPU architecture is Fermi. Note that CUDA is capable of running only on x64 machines.

Building

Prerequisites: Properly installed CUDA version 7 or newer. To download the CUDA SDK visit https://developer.nvidia.com/cuda-downloads
Enable CUDA support: When CMake detects CUDA (usually done automatically when CUDA is properly installed), a CMake option BUILD_CUDA becomes available. If this option is chosen then the compiled binary will be capable of running on CUDA devices.

Running

Prerequisites

nVIDIA driver supporting CUDA 7 (note: I think a version 350 or higher should do)
EACirc binary compiled with CUDA support

Configuration

Enable CUDA (option EACIRC/CUDA/ENABLED is set to 1).
Use Gate 2 circuit backend (option EACIRC/MAIN/CIRCUIT_REPRESENTATION is set to 3).
Disable circuit memory (option EACIRC/GATE_CIRCUIT/USE_MEMORY is set to 0).
Disable JVMSim functionality (option EACIRC/GA_CIRCUIT/ALLOWED_FUNCTIONS/FNC_JVM is set to 0).
Parameter EACIRC/TEST_VECTORS/SET_SIZE should be at least 32000 (any other number will do, but a multiple of cuda block size is the most effective).

Advanced Configuration

Note: Changing these options could dramatically increase or decrease the effectiveness of CUDA circuit. (If you don't know what you are doing decrease is most likely.)

option EACIRC/CUDA/BLOCK_SIZE - size of the block in kernel (default is 512)
option EACIRC/TEST_VECTORS/SET_SIZE - number of running threads in kernel
If any of the following options is changed then it is recommended to experimentally find the most effective settings for CUDA circuit (block size and test set size).
- EACIRC/MAIN/CIRCUIT_SIZE_INPUT
- EACIRC/MAIN/CIRCUIT_SIZE_OUTPUT
- EACIRC/GATE_CIRCUIT/NUM_LAYERS
- EACIRC/GATE_CIRCUIT/SIZE_LAYER
- EACIRC/GATE_CIRCUIT/NUM_CONNECTORS
EACIRC/MAIN/SAVE_STATE_FREQ any number higher than 100 will do, preferably 1000