Is unified memory on Mac Studio M2 Ultra 64GB as fast as VRAM for Kimi Linear 48B A3B?

Not always. Mac Studio M2 Ultra 64GB 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.

Can Kimi Linear 48B A3B run on Mac Studio M2 Ultra 64GB?

YES — Tight Fit

A81Great

Estimated from fit model

Kimi Linear 48B A3B needs ~38.9 GB VRAM. Mac Studio M2 Ultra 64GB has 46.1 GB. With Q4_K_M quantization, expect ~16 tok/s.

Runtime: TransformersCapacity: TightBandwidth: HighStack: StandardBottleneck: Balanced

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) — 38.9 GB, 15.8 tok/s, Tight fit

38.9 GB required46.1 GB available

84% VRAM used

Fit status

Tight fit

Decode

15.8 tok/s

TTFT

12217 ms

Safe context

140K

Memory

38.9 GB / 46.1 GB

Memory breakdown

Weights29.3 GB

KV Cache0.9 GB

Runtime1.8 GB

Headroom6.9 GB

See how fast it feels

See how fast it feelsKimi Linear 48B A3B on Mac Studio M2 Ultra 64GB
1st promptCold start — includes initialization
>Write a Python function to sort a list
Here's a Python function that sorts a list using quicksort:

def quicksort(arr):
    if len(arr) <= 1:
        return arr
    pivot = arr[len(arr) // 2]
    left   = [x for x in arr if x < pivot]
    middle = [x for x in arr if x == pivot]
    right  = [x for x in arr if x > pivot]
    return quicksort(left) + middle + quicksort(right)

# Example usage
numbers = [3, 6, 8, 10, 1, 2, 1]
print(quicksort(numbers))  # [1, 1, 2, 3, 6, 8, 10]

The algorithm picks a pivot, partitions the list into smaller, equal, and larger elements, then recursively sorts each partition and concatenates the results.
2nd promptWarm — model ready, no init overhead
>Now add type hints and a docstring
def quicksort(arr: list[int]) -> list[int]:
    """Sort a list using the quicksort algorithm.

    Args:
        arr: List of integers to sort.

    Returns:
        A new sorted list.
    """
    if len(arr) <= 1:
        return arr
    pivot = arr[len(arr) // 2]
    left   = [x for x in arr if x < pivot]
    middle = [x for x in arr if x == pivot]
    right  = [x for x in arr if x > pivot]
    return quicksort(left) + middle + quicksort(right)

Added type hints for the input and return type, plus a Google-style docstring.
Estimated: 15.8 tok/s decode · 12.2s TTFT (warm) · 40 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

Workload	Grade	Fit	Decode	TTFT	Context
Chat	A	Tight fit	15.8 tok/s	6664 ms	140K
Coding	A	Tight fit	15.8 tok/s	12217 ms	140K
Agentic Coding	A	Tight fit	15.8 tok/s	17770 ms	140K
Reasoning	A	Tight fit	15.8 tok/s	14438 ms	140K
RAG	A	Tight fit	15.8 tok/s	22212 ms	140K

Quantization options

How Kimi Linear 48B A3B (48B params) fits at each quantization level on Mac Studio M2 Ultra 64GB (46.1 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	18.7 GB	Low	A79
Q3_K_S	3	23.5 GB	Low	A81
NVFP4	4

Get started

Copy-paste commands to run Kimi Linear 48B A3B on your machine.

Run

docker run --rm -it ghcr.io/ggerganov/llama.cpp:full \
  --hf-repo "moonshotai/Kimi-Linear-48B-A3B-Instruct" \
  --hf-file "Kimi-Linear-48B-A3B-Instruct-Q4_K_M.gguf" \
  -c 4096 -ngl 99

Frequently asked questions

Can Mac Studio M2 Ultra 64GB run Kimi Linear 48B A3B?

Yes, Mac Studio M2 Ultra 64GB can run Kimi Linear 48B A3B with a A grade (Tight fit). Expected decode speed: 15.8 tok/s.

How much VRAM does Kimi Linear 48B A3B need?

Kimi Linear 48B A3B (48B parameters) requires approximately 38.9 GB of memory with Q4_K_M quantization.

What is the best quantization for Kimi Linear 48B A3B?

The recommended quantization for Kimi Linear 48B A3B is Q4_K_M, which balances quality and memory efficiency.

What speed will Kimi Linear 48B A3B run at on Mac Studio M2 Ultra 64GB?

On Mac Studio M2 Ultra 64GB, Kimi Linear 48B A3B achieves approximately 15.8 tokens per second decode speed with a time-to-first-token of 12217ms using Q4_K_M quantization.

Can Mac Studio M2 Ultra 64GB run Kimi Linear 48B A3B for coding?

For coding workloads, Kimi Linear 48B A3B on Mac Studio M2 Ultra 64GB receives a A grade with 15.8 tok/s and 140K context.

What context window can Kimi Linear 48B A3B use on Mac Studio M2 Ultra 64GB?

On Mac Studio M2 Ultra 64GB, Kimi Linear 48B A3B can safely use up to 140K tokens of context. The model's official context limit is 1.0M, but available memory constrains the safe maximum.

See all results for Mac Studio M2 Ultra 64GB See all hardware for Kimi Linear 48B A3B

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