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GLM / Lab profile

Z.ai

Track the attention changes separately from the post-training gains.

GLM’s 2026 releases show why a version number is not an architecture description. The smaller GLM-4.7-Flash, the 744B-class GLM-5 line and the 320B GLM-5.3-Flash occupy different deployment classes. Within the flagship line, later training and attention changes deserve separate evaluation.

Architecture trajectory

What connects these models?

GLM-5 uses sparse attention at large MoE scale. GLM-5.2 introduces IndexShare across layers; GLM-5.3 builds on that base through post-training. GLM-5.3-Flash instead combines KDA with sparse latent attention and index pooling, adding native visual input in a smaller total-parameter class.

Two kinds of layers retain two kinds of state.

A token enters a layerthe layer type selects its pathRecurrent layerupdate a compact stateAttention layerread retained token historyRecurrent statemaintained for this sequenceAttention cachelayout depends on the model

Hybrid attention does not mean zero request state.

A full-attention formula cannot describe every layer.

Schematic of a hybrid attention stack, not a literal layer ordering. Recurrent layers update a compact state; attention layers retain their own history. Both kinds of state matter for prefix reuse and concurrent requests.

Newest first / grouped sequence, not a time scale

The GLM timeline

  1. GLM-5.3-Flash

    Smaller than GLM-5.3, still a multi-GPU model

    The model combines Kimi Delta Attention with sparse latent attention and index pooling. Supporting those operators matters more than whether a server can merely load an FP8 tensor file.

    This is the dated Z.ai release-note event; a separate first weight-upload day has not been certified.

    Release evidence ↗

  2. GLM-5.3

    A post-training release with a changed adoption decision

    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 ↗

  3. GLM-5.2

    A million-token setting backed by index sharing

    Index sharing reuses selection work across layers. It changes the implementation and memory-access pattern, but a million configured positions still require a realistic request budget and a long-context quality test.

    This is the dated Z.ai release-note event; a separate first weight-upload day has not been certified.

    Release evidence ↗

  4. GLM-5.1

    Longer agent runs need process-level evaluation

    The release focuses on planning and iterative refinement. The vLLM guide reports the same approximate 744B/40B size class, so deployment scale remains substantial even when post-training changes task behavior.

    This is the dated Z.ai release-note event; a separate first weight-upload day has not been certified.

    Release evidence ↗

  5. GLM-5

    A large sparse-attention foundation for the GLM line

    The release emphasizes longer engineering and agent tasks. Later checkpoints refine training and attention behavior, which makes the family a good study of improvement without treating every decimal version as a new size class.

    This is the dated Z.ai release-note event; a separate first weight-upload day has not been certified.

    Release evidence ↗

  6. GLM-4.7-Flash

    A compact way to learn latent-attention serving

    The January release occupies a different deployment class from the later 320B GLM-5.3-Flash. “Flash” is a product-family label, not a stable size or latency category.

    This is the dated Z.ai release-note event; a separate first weight-upload day has not been certified.

    Release evidence ↗

Which other labs should you compare?

Compare 5.2 with 5.3 to study post-training at a similar base scale. Compare Flash with Qwen3.8-Flash-Next for visual agent workloads. For coding, Kimi K2.7-Code is a useful independent candidate, provided the tool harness and reasoning budgets match.

Kimi

Moonshot AI

Follow the jump from a coding update to a new attention stack.

Qwen

Alibaba Qwen

One family spans tiny dense models, coding MoEs and conditional memory.

Interview preparation

What you should be able to explain

Draw the sparse-attention index, selected reads and retained cache as separate objects. Then explain why a model can improve coding results through post-training without reducing serving memory.

Study the underlying systems → · Get the illustrated report →

Sources and scope

Checked 13 September 2026. Assessments and comparison candidates are our interpretation of the cited designs, not measured cross-lab rankings. Each timeline entry links to its release evidence; model pages preserve pinned card and configuration sources.