Introduction

Efficient data transfer between host and device memory is critical for optimal CUDA performance. Proper management reduces latency and maximizes bandwidth utilization. 📈

Key Concepts

  • Device Memory: Directly accessed by GPU cores for parallel computations.

    device_memory
  • Host Memory: Managed by the CPU, requires explicit copying to device memory.

    host_memory
  • Unified Memory: Simplifies data sharing with automatic memory management (CUDA 6.0+).

    unified_memory

Best Practices

  1. Use cudaMemcpy: For direct data transfers between host/device memory.

    cuda_memcpy
  2. Avoid Frequent Copies: Minimize memory transfers by reusing buffers.

    avoid_frequent_copies
  3. Leverage Asynchronous Transfers: Overlap data movement with computation using streams.

    async_transfer

Performance Optimization

  • Memory Bandwidth: Prioritize cudaMemcpyPeer for peer-to-peer transfers between GPUs.
  • Memory Allocation: Pre-allocate memory with cudaMalloc to reduce overhead.
  • Parallelism: Use cudaMemcpyAsync with multiple streams for concurrent transfers.

For advanced techniques, check our CUDA Memory Optimization Guide. 📚

Tools & Resources

cuda_data_flow