Thread Hierarchy

Thread Organization

CUDA organizes threads in a hierarchical structure:

• Thread: The basic unit of execution
• Block: A group of threads that can cooperate
• Grid: A collection of blocks that execute the same kernel
• Warp: A group of 32 threads that execute together

Thread Indexing Example

Here's an example showing how to work with thread and block indices:

Thread Synchronization

CUDA provides several synchronization mechanisms:

• __syncthreads() - Synchronizes all threads in a block
• cudaDeviceSynchronize() - Synchronizes the host with the device
• Atomic operations for thread-safe memory access
• CUDA events for asynchronous operation synchronization