GPUnet is a native GPU networking layer that provides a reliable stream abstraction over Infiniband and high-level socket APIs to GPU programs for NVIDIA GPUs.

GPUnet enables threads or threadblocks in one GPU to communicate with threads in other GPUs or CPUs via standard and familiar socket interfaces, regardless of whether they are in the same or different machines.

GPUnet uses Peer-to-Peer DMA (via GPUDirectRDMA) to place and manage network buffers of a GPU application directly in GPU memory.

This is a code example of a simple (working) GPU echo client.

Note that the GPU socket API is threadblock-cooperative, meaning that all the threads in the threadblock are required to call the same function with the same parameters at the same point in a program.

__global__ void gpuclient(struct sockaddr_in *addr, int* tb_alloc_tbl, int nr_tb) {
  __shared__ int sock;
  __shared__ uchar buf[BUF_SIZE];
  int ret, i;

  while ((sock = gconnect_in(addr)) < 0) {};
  assert(sock >= 0);

  for (i = 0; i < NR_MSG; i++) {
    int recved = 0, sent = 0;

    do {
      ret = gsend(sock, buf + sent, BUF_SIZE - sent);
      if (ret < 0) {
        goto out;
      } else {
        sent += ret;
      }
    } while (sent < BUF_SIZE);
    
    __syncthreads(); 
  
    do {
      ret = grecv(sock, buf + recved, BUF_SIZE - recved);
      if (ret < 0) {
        goto out;
      } else {
        recved += ret;
      }
    } while (recved < BUF_SIZE);
    
    __syncthreads();
  }

  out:
  BEGIN_SINGLE_THREAD_PART {
      single_thread_gclose(sock);
  } END_SINGLE_THREAD_PART;
}

• CUDA 5.5
• CUDA driver 331.38 or higher
• Mellanox OFED 2.0
• Our modules are tested on CentOS 6.5.

To figure out any issues with configuration, you can run utils/diagnose.sh.

Before compiling, please add your GPU and CUDA compilation option to the bottom case statements of utils/nvcc_option_gen.sh. Adding an entry significantly reduces compilation time.

For compilation of gpunet, rsocket for GPUnet needs to be installed first. It is located under core/rsocket. There, execute the following:

./osa_config.sh; make; make install

Then we need the gpu_usermap driver. Its location is under core/gpu_usermap. Similar make and make install will do the job.

You can then compile the GPUnet library by running make under the core directory.

You can use applications in apps/microbenchmark for testing.