Fix cudaErrorMpsConnectionFailed: MPS Server Connection Error

Overview

cudaErrorMpsConnectionFailed occurs when unable to connect to NVIDIA Multi-Process Service server.

Error Messages

CUDA error: MPS connection failed
cudaErrorMpsConnectionFailed

Common Causes

• •MPS server not running
• •MPS pipe not accessible
• •Permission issues
• •Wrong CUDA_MPS_PIPE_DIRECTORY

Solutions

export CUDA_VISIBLE_DEVICES=0
nvidia-cuda-mps-control -d

echo get_server_list | nvidia-cuda-mps-control

Prevention Tips

• ✓Start MPS before applications
• ✓Check permissions on MPS pipe directory

Code Examples

Before (Problematic)

MPS daemon required.

// Running with MPS but daemon not started

After (Fixed)

Daemon running.

# Start MPS daemon first
nvidia-cuda-mps-control -d
# Then run application

Frequently Asked Questions

Related Errors

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