willitrun·ai

Can Gemma 2 9B run on Mac Studio M2 Ultra 128GB?

YES — Runs Great

B61Good
Estimated from fit model

Gemma 2 9B needs ~25.3 GB VRAM. Mac Studio M2 Ultra 128GB has 92.2 GB. With Q4_K_M quantization, expect ~67 tok/s.

Runtime: llama.cppCapacity: RoomyBandwidth: HighStack: StandardBottleneck: Balanced
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Operating mode

Choose the run profile you care about

Interactive favors responsiveness, while light API and scale-out lean harder on serving readiness. The fit stays the same, but the recommendation lens changes.

Current mode

Balanced

Balanced for general local use. Keeps the ranking neutral across personal and serving workflows.

Capabilities:

Select quantization to explore

Q4_K_M (Medium quality) 25.3 GB, 67.3 tok/s, Runs well
25.3 GB required92.2 GB available
27% VRAM used

Fit status

Runs well

Decode

67.3 tok/s

TTFT

2879 ms

Safe context

8K

Memory

25.3 GB / 92.2 GB

Memory breakdown

Weights5.5 GB
KV Cache5.1 GB
Runtime0.9 GB
Headroom13.8 GB

See how fast it feels

See how fast it feelsGemma 2 9B on Mac Studio M2 Ultra 128GB
1st promptCold start — includes initialization
>What is local AI inference?
Local AI inference means running an AI language model directly on your own hardware — your laptop, desktop, or server — instead of sending requests to a remote cloud API. When you run inference locally the model weights are loaded into your GPU or unified memory. Each token you generate requires reading those weights from memory, so memory bandwidth is the main bottleneck for decode speed. Key benefits of running locally: - Full privacy: your prompts never leave your machine - No per-token cost or rate limits - Works offline once the model is downloaded - Latency depends only on your hardware
2nd promptWarm — model ready, no init overhead
>How much VRAM do I need?
It depends on the model size and quantization level. A rough rule of thumb: Model size Q4 (4-bit) Q8 (8-bit) FP16 7B params ~4.3 GB ~7.5 GB ~14 GB 13B params ~7.9 GB ~13.9 GB ~26 GB 70B params ~42.7 GB ~74.9 GB ~140 GB Most people use 4-bit quantization (Q4_K_M) which gives 90-95% of full quality at a fraction of the memory. A 24 GB GPU can comfortably run most 7B-13B models.
Estimated: 67.3 tok/s decode · 2.9s TTFT (warm) · 168 tok/s prefill

What limits this setup

This setup is broadly balanced for this model.

Shared-memory contention still exists

The OS, browser, and inference runtime all compete for the same physical memory pool, so real-world headroom is less forgiving than raw capacity suggests.

Best improvement path

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatBRuns well67.3 tok/s1570 ms8K
CodingBRuns well67.3 tok/s2879 ms8K
Agentic CodingBRuns well67.3 tok/s4187 ms8K
ReasoningBRuns well67.3 tok/s3402 ms8K
RAGBRuns well67.3 tok/s5234 ms8K

Inference speed

Gemma 2 9B inference speed — tokens per second by GPU & Mac

Estimated decode speed (tokens/sec) for Gemma 2 9B at Q4_K_M across popular GPUs and Apple Silicon, using the fastest local runtime per device. Fastest is RTX 5090 32GB at ~126 tok/s. Speed is memory-bandwidth bound, so cards that fit the whole model in VRAM run far faster than ones that offload to system RAM.

GPU / MacMemoryQuantSpeed (tok/s)Fits?
NVIDIARTX 5090 32GB
32 GBQ4_K_M126.0Fits
NVIDIARTX 4090 24GB
24 GBQ4_K_M126.0Fits
NVIDIARTX 3090 24GB
24 GBQ4_K_M125.3Fits
RX 7900 XTX 24GB
24 GBQ4_K_M86.6Fits
Mac Studio M3 Ultra 256GB
256 GBQ4_K_M80.7Fits
NVIDIARTX 4080 Super 16GB
16 GBQ4_K_M78.2Fits
MacBook Pro M4 Max 64GB
64 GBQ4_K_M71.7Fits
Mac Studio M2 Ultra 128GB
128 GBQ4_K_M67.3Fits
Mac Studio M1 Ultra 128GB
128 GBQ4_K_M63.8Fits
MacBook Pro M4 Max 128GB
128 GBQ4_K_M54.3Fits
MacBook Pro M3 Max 64GB
64 GBQ4_K_M45.9Fits
NVIDIARTX 4070 12GB
12 GBQ4_K_M45.7Heavy offload
MacBook Pro M1 Max 64GB
64 GBQ4_K_M42.1Fits
MacBook Pro M4 Pro 48GB
48 GBQ4_K_M37.0Fits
NVIDIARTX 3060 12GB
12 GBQ4_K_M28.7Heavy offload
NVIDIARTX 4060 8GB
8 GBQ4_K_M10.9Too big

Estimates for single-stream decoding at Q4_K_M; real tokens/sec varies with prompt length, context, batch size, and runtime build. Prompt processing (prefill) is faster than the decode figures shown here.

Quantization options

How Gemma 2 9B (9B params) fits at each quantization level on Mac Studio M2 Ultra 128GB (92.2 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
3.5 GB
LowC54
Q3_K_S
3
4.4 GB
LowC54
NVFP4
4
5.0 GB
MediumC54
Q4_K_M
4
5.5 GB
MediumC54
Q5_K_M
5
6.5 GB
HighC54
Q6_K
6
7.4 GB
HighC54
Q8_0
8
9.6 GB
Very HighC54
F16Best for your GPU
16
18.5 GB
MaximumB55

Get started

Copy-paste commands to run Gemma 2 9B on your machine.

Run

ollama run gemma2

Frequently asked questions

Can Mac Studio M2 Ultra 128GB run Gemma 2 9B?

Yes, Mac Studio M2 Ultra 128GB can run Gemma 2 9B with a B grade (Runs well). Expected decode speed: 67.3 tok/s.

How much VRAM does Gemma 2 9B need?

Gemma 2 9B (9B parameters) requires approximately 25.3 GB of memory with Q4_K_M quantization.

What is the best quantization for Gemma 2 9B?

The recommended quantization for Gemma 2 9B is Q4_K_M, which balances quality and memory efficiency.

What speed will Gemma 2 9B run at on Mac Studio M2 Ultra 128GB?

On Mac Studio M2 Ultra 128GB, Gemma 2 9B achieves approximately 67.3 tokens per second decode speed with a time-to-first-token of 2879ms using Q4_K_M quantization.

Can Mac Studio M2 Ultra 128GB run Gemma 2 9B for coding?

For coding workloads, Gemma 2 9B on Mac Studio M2 Ultra 128GB receives a B grade with 67.3 tok/s and 8K context.

What context window can Gemma 2 9B use on Mac Studio M2 Ultra 128GB?

On Mac Studio M2 Ultra 128GB, Gemma 2 9B can safely use up to 8K tokens of context. The model's official context limit is 8K, but available memory constrains the safe maximum.

Is unified memory on Mac Studio M2 Ultra 128GB as fast as VRAM for Gemma 2 9B?

Not always. Mac Studio M2 Ultra 128GB can often fit larger models thanks to unified memory, but a discrete GPU with dedicated high-bandwidth VRAM may still decode faster once the model fits. For this combination, the important distinction is capacity versus sustained throughput.

See all results for Mac Studio M2 Ultra 128GBSee all hardware for Gemma 2 9B
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