Replicate or cooperate · 11 min
Inference across multiple GPUs
Replicas serve independent requests, while tensor, pipeline, or expert parallelism make several GPUs cooperate on one model.
Plain language, the core causal flow, and required checks.
More capacity has more than one meaning
Independent replicas each hold a complete model and serve different requests. They increase aggregate throughput but do not help an oversized model fit on one device.
Model-parallel approaches make several GPUs cooperate on one request. Tensor parallelism divides operations within layers; pipeline parallelism divides layers; expert parallelism routes tokens among expert partitions.
Cooperation introduces communication and synchronization. The useful question is not simply “How many GPUs?” but whether they are replicating work or sharing one model execution.
Interactive explanation
Compare multi-GPU strategies
Multi-GPU inference
See exactly when GPUs work independently or communicate
Every strategy uses the same GPU cards. The request placement and communication paths change to match the selected execution model.
- Distinguish replication from model parallelism.
- Explain why model fit, capacity, or latency can require more GPUs.
Core check
Which setup makes GPUs communicate while serving one model?
Terms in this chapter
- Tensor parallelism
- A strategy that partitions a model operation across devices that must exchange partial results.
Primary references
- Tensor Parallelism ↗PyTorch
Primary framework reference for tensor-parallel module plans.