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models / google/gemma-4-12B
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12B paramsbfloat16GQA 16:8262K ctxmultimodalapache-2.0
Sparks
Users
~45 GB
~39 GB
~33 GB
~27 GB
~24 GB
110 usable
Spec decode
Context33K / 262KKV
On the Sparks — 1× · 1-bit GGUF (dynamic) · 33K ctx · FP16 KV~251K ctx fits usable · ~7 users fit
spark
86 GB free
KV cache12.9* GBFP16
110 usable
24* / 110 GB
22% of usable
Dense weightsKV cacheActivations + graphsOS reserve

* segment sizes marked with an asterisk are estimates pending a measured run

Estimated per-node footprint, weights + KV sharded across the Spark (tensor parallel). Overhead ~8 GB/node; KV at FP16.

layer map
48 layerssliding window×40full attention×8
in
out
all 48 layers fire per token — 12.0B active
Optimize
Verdict

12B params, ~24 GB at bfloat16 — fits on one Spark as-is.

Make it fit

Get the weights (and headroom for KV) inside the 128 GB pool — the hard gate.

Lossless compression

BF16 weights entropy-code ~30% smaller bit-exact — smaller downloads and less bandwidth per token, no quality question at all.

Make it fast

Once it fits: fewer bytes per token and fewer decode steps against 273 GB/s.

Add a speculative decoder

Decode is bandwidth-bound at ~11.4 tok/s ceiling; a trained EAGLE-style draft multiplies tokens per weight-read.

Make it yours

Change what the model does — adapt, edit, or steer it — independent of size.

Fine-tune it

LoRA/QLoRA adapts behavior on one Spark without touching the base weights.