I'm working on a project where I distribute compute tasks to multiple python Processes each associated with its own CUDA device.
When spawning the subprocesses, I use the following code:
import pycuda.driver as cuda
class ComputeServer(object):
def _init_workers(self):
self.workers = []
cuda.init()
for device_id in range(cuda.Device.count()):
print "initializing device {}".format(device_id)
worker = CudaWorker(device_id)
worker.start()
self.workers.append(worker)
The CudaWorker is defined in another file as follows:
from multiprocessing import Process
import pycuda.driver as cuda
class CudaWorker(Process):
def __init__(self, device_id):
Process.__init__(self)
self.device_id = device_id
def run(self):
self._init_cuda_context()
while True:
# process requests here
def _init_cuda_context(self):
# the following line fails
cuda.init()
device = cuda.Device(self.device_id)
self.cuda_context = device.make_context()
When I run this code on Windows 7 or Linux, I have no issues. When running the code on my MacBook Pro with OSX 10.8.2, Cuda 5.0, and PyCuda 2012.1 I get the following error:
Process CudaWorker-1:
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
self.run()
File "/Users/tombnorwood/pymodules/computeserver/worker.py", line 32, in run
self._init_cuda_context()
File "/Users/tombnorwood/pymodules/computeserver/worker.py", line 38, in _init_cuda_context
cuda.init()
RuntimeError: cuInit failed: no device
I have no issues running PyCuda scripts without forking new processes on my Mac. I only get this issue when spawning a new Process.
Has anyone run into this issue before?
