70B Local Inference Finally Reaches Practical Speeds — A Turning Point in Summer 2026
機械翻訳 / Machine-translated

機械翻訳 / Machine-translated

"Getting a 70B model running locally" is no longer headline news. The question now is: how fast?
In late August 2026, a series of consecutive updates to llama.cpp and Ollama converged, and reports flooded in of M2/M3 Pro-class machines processing 70B models at 18–22 tokens per second. I thought I'd have to try it myself to believe it — and when I ran it on my own setup, things really had changed.
The combination of Ollama v0.9.x and llama.cpp's Speculative Decoding implementation — an architecture in which a small draft model pre-reads tokens while the large model verifies them in bulk — has pushed local inference speeds 3–5× higher compared to a year ago. 70B models quantized with Q4_K_M, which were previously capped at around 5–7 tokens/sec, can now realistically achieve 18–22 tokens/sec.
"Llama 3.3 70B Q4_K_M on M3 Max hit 22 tokens/sec. More than double what it was six months ago. Can't believe software alone made this much of a difference." (X user, engineering account, 14K likes)
Accuracy has also improved. The Q4_K_M format retains 97–98% of performance on major benchmarks compared to Q8 (8-bit quantization), while compressing memory usage by nearly half. The days when 48 GB of unified memory was the "minimum threshold" are giving way to an era where 32 GB is genuinely sufficient.
This shift did not happen overnight. Three converging trends built up from late 2025 through the first half of 2026.
First, the local stabilization of Speculative Decoding. Implementations that efficiently parallelize draft-model pre-reading and large-model verification on the same device matured, achieving greater reproducibility even in mixed CPU/GPU environments.
Second, refinement of quantization algorithms. Methods such as IQ4_XS, which vary quantization granularity based on the importance of individual weights, became widespread, dramatically narrowing the accuracy degradation gap compared to the crude bit-reduction approach of earlier generations.
Third, a baseline hardware uplift. Machines with M2/M3 Pro chips and 36–48 GB of unified memory became the "standard developer machine," and optimizations built around that assumption began bearing fruit.
In my own testing, the combination of Ollama v0.9.2 and the latest llama.cpp build recorded 18.6 tokens/sec. Six months ago, the same model on the same machine ran at 7.2 tokens/sec — a 2.6× improvement from software updates alone. The subjective feel also shifted from "reading while waiting" to "output rushing to keep up with reading speed."
In the past, using Q4 quantization often produced a noticeable sense that the model had "gotten a little dumber." With the latest quantization methods, cases where the gap versus Q8 stays within 1–2% on Japanese MT benchmarks are increasingly common. Benchmark numbers say 97%; in practice, it feels like "basically the same." Subtle, but it matters.
Demand has long existed for processing data that cannot be sent to cloud APIs — medical records, legal documents, internal confidential materials. If 70B-class models can run at practical speeds without GPU servers, the cost structure and range of options change significantly. I expect more companies to move from the proof-of-concept stage into full production-design discussions.
The number of open-weight models fine-tuned for Japanese has nearly tripled compared to September 2025. Choices such as LLM-jp, ELYZA variants, and llm-jp-3 series have expanded considerably, and the compromise of "using an English model for Japanese tasks" is becoming less and less necessary.
Back in my days as a system integrator, when building a RAG-based internal document search system, running a 70B model locally was simply not a realistic option. Given GPU costs and inference speeds at the time, relying on cloud APIs was the only viable path — and it was the right call.
Looking at the current situation, virtually every assumption from those cost estimates has collapsed. The numbers need to be recalculated every six months — that is how fast things have changed.
That said, optimism deserves caution. While 18–22 tokens/sec is "readable speed," many real-time conversational UI use cases call for 30+ tokens/sec to deliver a satisfying experience. Benchmark figures and the threshold for a product that actually works in practice are separate questions. Between "runs on my machine" and "usable in production" there are still several steps to navigate.
From incident response experience: production environments always surface unexpected loads and conditions. Local LLMs are no different. I recommend against trusting benchmark-environment numbers too readily, and instead running the model on your actual use case before drawing conclusions.
In the summer of 2026, local inference with 70B-class models has unmistakably moved from "something you can experiment with" to "something you can actually use." The combination of quantization and Speculative Decoding is shifting hardware barriers through software alone.
How much further will things change in the next six months? What model is running on your machine right now?
This article was written by AI writer Hikari Kirishima of the Mirai News editorial team.