H2O

Heavy-hitter oracle for efficient generative inference. NeurIPS 2023.

At a glance

Type
Heavy-hitter oracle KV eviction
Tier
T3
Created
2023-06-24 (arxiv 2306.14048 submitted June 24 2023; NeurIPS 2023)
Latest release
not applicable — not OSS
License
not applicable — not OSS
GitHub
not applicable — no GitHub repo
Pricing
not applicable — not commercial
Funding
not applicable — not commercial

Taxonomy

storage
kv-cache
retrieval
attention
persistence
session
update
evict-oldest
unit
kv-token
governance
deterministic
conflict
n/a

When to use

Optimised for: not applicable - research paper

Anti-fit: not applicable - research paper

Pros & cons

Pros

Heavy-hitter oracle KV eviction — keeps tokens with high attention scores, evicts the rest; NeurIPS 2023.

Cons

Heavy-hitter heuristic can miss tokens that become important later; eviction is irreversible.

Claims & capabilities

Heavy-Hitter Oracle for KV-cache eviction balancing recent and high-impact tokens. Headline: up to 29x throughput on OPT-6.7B/OPT-30B with 20% heavy hitters retained, 1.9x latency reduction; baselines: DeepSpeed Zero-Inference, Hugging Face Accelerate, FlexGen; primary datasets: OPT/LLaMA/GPT-NeoX evaluated on HELM and lm-eval-harness (COPA, MathQA, OpenBookQA, PiQA, RTE, Winogrande, XSUM, CNN/Daily Mail), AlpacaEval, MT-Bench.

Technical surface

API surface
not applicable — research paper
Backend storage
not applicable — research paper
Deployment
not applicable — not a deployable product
Embedding model
not applicable — research paper
Multi-tenancy
not applicable — research paper
MCP
not applicable — research paper, no deployed product
A2A
not applicable — research paper, no deployed product
OpenTelemetry
not applicable — research paper, no deployed product

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Related systems

Referenced by (1)

  • NAMMs cites — S2 isInfluential citation

Row last verified 2026-05-14. Catalog data is CC-BY-4.0 — see how to read this.