Introduction: Why Caching is Critical for LLM Performance

In the era of large language models (LLMs), where models like GPT-4 and Llama process billions of parameters, efficiency is paramount. LLMs excel at generating human-like text, but their inference phase—generating responses token by token—can be computationally intensive and costly. Enter caching mechanisms: these are like the short-term memory of LLMs, storing intermediate computations to avoid redundant work. Without caching, every new token generation would recompute the entire context, leading to skyrocketing latency and expenses.
LMCache, an open-source KV cache layer, exemplifies this by enabling LLMs to prefill text only once and reuse KV caches for any repeated text segments, not just prefixes. This reduces time-to-first-token (TTFT) and GPU usage, making it ideal for long-context scenarios. For enterprises deploying AI agents, caching isn’t just a nice-to-have—it’s essential for scaling operations while controlling costs. In this blog, we’ll dive into LMCache and broader caching strategies, exploring their mechanics, benefits, and future in agentic AI.

  • Faster Inference Times: By reusing KV caches, it cuts TTFT by 3–10x in vLLM-integrated setups for multi-round QA.
  • Lower Compute and Memory Usage: Offloads to CPU/disk, freeing GPU for more requests—boosting throughput 3x.
  • Cost Optimization: Enterprises save on GPU hours: Redis integration enables scalable, low-cost caching.

Aspect

Without Caching

With LMCache/KV Caching

Latency (TTFT)

High (recomputes all tokens)

3–10x lower (reuses caches)

Throughput

Low (limited by GPU)

3x higher (offloads memory)

Cost per Inference

High ($0.05–$0.20/1K tokens)

50–90% savings on repeats

Memory Usage

Scales quadratically

Optimized via quantization/offloading

Scalability

Poor for long contexts

Handles 1M+ tokens efficiently

KV caching stores intermediate attention computations for reuse in generation, while prompt caching saves entire prompt prefixes to avoid reprocessing.

By reusing KV caches, it minimizes GPU cycles and inference time, leading to 50–90% savings on repeated computations in workflows like RAG.

Key issues include storage overhead for large contexts, invalidation in dynamic scenarios, and maintaining consistency across distributed systems.

About lowtouch.ai

lowtouch.ai delivers private, no-code AI agents that integrate seamlessly with your existing systems. Our platform simplifies automation and ensures data privacy while accelerating your digital transformation. Effortless AI, optimized for your enterprise.

2025
Agentic AI
2nd – 3rd October

New York City, USA

Promptstash
Chrome extension to manage and deploy AI prompt templates.
works with chatgpt, grok etc

Effortless way to save and reuse prompts