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GLM / MoE

GLM-5.3

A post-training release with a changed adoption decision

AnnouncementSources checked 2026-09-13

GLM-5.3 should be evaluated as a coding-focused update to the GLM-5.2 base, with license and safety-release changes reviewed separately. It is not evidence that every capability gain required a larger pretrained model.

743Breported total parameters
39Bactive parameters per token
1,048,576configured token positions

Approximate 743B total / 39B active, as reported in the model-specific vLLM guide; not an exact tensor inventory.

Evaluate it for

Controlled coding-agent and authorized defensive-security evaluations on a cluster.

Choose another path when

Inheriting GLM-5.2’s MIT metadata without reading the current checkpoint’s custom terms.

Release context

Why this release matters

The card attributes the update to post-training and highlights cyber-defense evaluations. Hosted access and weights did not arrive together; this history matters when reproducing comparisons or dating adoption.

The pinned card dates its launch comparison August 14; the API release notes are dated August 18. Weights were staged later; do not treat August 14 as their upload date.

Release evidence · Announced 2026-08-14 · Follow the GLM 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.

755.62 GB of tensor data in the pinned index

This is the index’s reported tensor payload, in decimal GB. It excludes file headers and runtime memory. Mixed precision, conversion and host/device placement determine how much GPU memory the loaded model needs.

Inspect the exact index metadata →
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. Approximate 743B total / 39B active, as reported in the model-specific vLLM guide; not an exact tensor inventory. Use the documented artifact and placement path above; no GPU count is inferred here.

Architecture in practice

What the serving engine has to do

Store the history. Read the selected parts.

Retained KV historyall state required by the modelIndex / selectionfind relevant blocksSelected KV blocksa subset of the retained historyAttention outputcomputed from selected reads

Fewer bytes read can reduce bandwidth pressure.

That does not prove an equal reduction in stored bytes.

Schematic of block-sparse attention. The indexer selects relevant blocks; attention reads those blocks from retained state. Index sharing can reuse selection work across layers. Read traffic, index work and allocated KV capacity are separate quantities.

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 checkpointzai-org/GLM-5.3
Text model typeglm_moe_dsa
Layers78
Hidden width6,144
Attention / KV heads64 / 64
Head dimension192
Routed / selected experts256 / 8
Configured positions1,048,576
Documented extensionNot recorded for this checkpoint
Inputs → outputtext → text
License metadataglm-5.3 · custom terms

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?

The earlier base lineage isolates the update; K2.7-Code provides an independent coding-focused comparison.

16 Jun 2026

GLM-5.2

A million-token setting backed by index sharing

743B reported total · text

12 Jun 2026

Kimi-K2.7-Code

A coding upgrade without a new size class

1,000B 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

Explain a controlled post-training comparison, including harness, reasoning budget and license constraints; keep benchmark gains separate from serving speed.

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, “GLM-5.3: release, architecture and deployment”, checked 2026-09-13. Preserve this date and the exact checkpoint when citing.

Model and research notes as JSON · Z.ai profile