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Gemma / Dense

gemma-4-E2B-it

“Effective” is a compute label, not the download size

Open-weight releaseSources checked 2026-09-13

E2B is interesting for constrained devices because it separates effective computation from per-layer embedding storage. Read its 2.3B effective and 5.1B inclusive counts together before selecting hardware.

5.1Breported total parameters
Denseactive parameters per token
131,072configured token positions

Includes per-layer embeddings; effective compute is smaller. Not a MoE active-parameter count.

Evaluate it for

Small-device text, vision and audio experiments with a supported Gemma runtime.

Choose another path when

A budget that reserves memory for only two billion parameters or copies a text-only conversion’s footprint onto the full model.

Release context

Why this release matters

Per-layer embedding tables are the reason the E label differs from a conventional dense parameter label. Placement and quantization of those tables can change the practical footprint substantially.

Release evidence · Follow the Gemma timeline →

Deployment starting points

Which hardware, how many, at what precision?

Start with an exact artifact and an engine that supports it. A configuration below is evidence of a documented path; its device count does not promise a particular throughput or concurrency.

No certified hardware configuration in this edition

A budget that reserves memory for only two billion parameters or copies a text-only conversion’s footprint onto the full model.

The pinned model card establishes the architecture. It does not, by itself, prove that a particular GPU count runs this checkpoint at your target context. The capacity screen below helps rule out undersized allocations; a successful load and workload test are still required.

Capacity screen: would the weights fit?

This estimates inference memory for a hypothetical uniform precision. It is useful for rejecting an allocation that is too small. It does not establish a working deployment or estimate training memory.

A uniform-precision GPU count would hide this model’s component layout. Includes per-layer embeddings; effective compute is smaller. Not a MoE active-parameter count. Use the documented artifact and placement path above; no GPU count is inferred here.

Architecture in practice

What the serving engine has to do

Shared tables and request cache have different lifetimes.

Shared model tablesn-gram, Engram or PLELookup pathselected entries for this tokenBackbone computationattention + feed-forward workRequest stateKV / recurrent cache

Model tables do not multiply with every request.

The lookup and host/device placement are model-specific.

Conditional model tables are shared across requests. A lookup selects entries, while the backbone executes the token computation. KV or recurrent state belongs to the request. Table offload and cache offload therefore solve different memory problems.

Mechanism schematic based on the pinned model card and configuration. It explains a design principle; it is not a full implementation graph.

Inspect the full checkpoint specifications
Inspected fields for this exact revision. KV heads alone do not describe latent, hybrid or shared-cache layouts.
Exact checkpointgoogle/gemma-4-E2B-it
Text model typegemma4_text
Layers35
Hidden width1,536
Attention / KV heads8 / 1
Head dimension256
Routed / selected expertsNot verified / Not verified
Configured positions131,072
Documented extensionNot recorded for this checkpoint
Inputs → outputtext, image, video, audio → text
License metadataapache-2.0

28 sliding attention layers; 7 full attention layers. These counts describe the configured pattern.

Open weights do not imply unrestricted use. Read the applicable license terms linked from the pinned card.

A useful comparison

What else belongs on the shortlist?

E4B tests additional capacity with the same design; Qwen2B provides a more conventional small-model comparison.

2 Apr 2026

gemma-4-E4B-it

More effective capacity, with tables still to place

8B reported total · text + image + video + audio

2 Mar 2026

Qwen3.5-2B

A small step up when the tiniest model misses too much

2B reported total · text + image + video

These are editorial comparison candidates. We have not run a matched quality or serving benchmark, so this is not a ranking.

Prepare to explain it

The interview lesson

Contrast shared model tables with per-request cache. Explain why offloading the former and the latter solve different problems.

Attention layouts · Quantization · Courses and worked examples

For a deployment evaluation, record exact weights, precision, engine, device count, interconnect, prompt/output lengths and concurrency. Report task success, errors, TTFT, TPOT and useful throughput together.

Sources and citation

Our assessment is editorial judgment based on the linked architecture and deployment evidence. Model facts are publisher-reported or attributed to runtime maintainers; no independent GPU benchmark was run.

AI Infra Interviews, “gemma-4-E2B-it: release, architecture and deployment”, checked 2026-09-13. Preserve this date and the exact checkpoint when citing.

Model and research notes as JSON · Google DeepMind profile