Overview
KV cache optimization addresses the memory bottleneck in autoregressive LLM inference. The cache stores key-value projections from attention layers for reuse across generation steps, avoiding redundant computation. However, cache size grows linearly with sequence length, creating memory constraints for long contexts.
Optimization techniques
- PagedAttention: Non-contiguous memory allocation
- KV compression: Reduce stored tokens
- KV retrieval: Selective cache reuse
- Quantization: Lower precision storage
- Speculative decoding: Reduce generation steps
Memory management
- CPU-GPU offload: Free GPU memory
- Chunked caching: Process in segments
- Sliding window: Limit context horizon
- Selective retention: Keep only key tokens
Key considerations
- Balance memory savings against quality loss
- Profile cache access patterns for optimization
- Consider hardware-specific implementations
- Handle cache invalidation for shared contexts