GLM-5.3-Flash EXL3 2.25bpw (GB10 / SM121 runtime)

EXL3 (ExLlamaV3 trellis) quantization of zai-org/GLM-5.3-Flash (320B total / ~18B active MoE) by r0b0tlab.

• Format: EXL3, ~2.25 bpw average, mul1 codebook, mixed K3/K4 tiles, output scales on, 6-bit head.
• Size: 98.5 GB (91.8 GiB) across 31 safetensors shards, plus quantization_config.json (full module/tensor manifest) and tokenizer files.
• Calibration: mixed corpus, tap-K3 selection.

Verified 256K long-context result (ExLlamaV3 runtime, 2026-09-27)

On a single GB10, our standalone ExLlamaV3 + TabbyAPI runtime (r0b0tlab/glm53-flash-exl3-exllamav3-gb10) with our EXL3 DFlash2 draft (r0b0tlab/GLM-5.3-Flash-DFlash2-EXL3-3.00bpw) served this pack at 262,144 tokens (FP16 KV, batch size 1, DFlash2 K=5) and passed a token-exact needle-in-a-haystack retrieval at 259,993 actual prompt tokens — clean answer, exact client/server token parity, guarded by an independent 6,144-MiB host-memory floor with no NVRM allocation failure.

Not qualified on that profile: multi-key output formatting, concurrency > 1, throughput at 256K, long-run stability. Details and sanitized evidence live in the runtime repository.

Serving

Two runtimes are available for this pack:

1. ExLlamaV3 / TabbyAPI (256K verified): r0b0tlab/glm53-flash-exl3-exllamav3-gb10 — native ARM64 CUDA 13 container, guarded 256K serve. Published image (ARM64/SM121): docker pull ghcr.io/r0b0tlab/glm53-flash-exl3-exllamav3-gb10:b25c467.

2. vLLM (32,768-token published profile): r0b0tlab/glm53-flash-exl3-dflash2-sm121 — host-native vLLM v0.30.0rc1 + EXL3 plugin; DFlash2 K=5 measured structured 50.2 / code 43.4 / prose 19.5 tok/s single-stream on one GB10. The two engines' results are independent; do not transfer between them.

Q200v2 quality kit on the ExLlamaV3 runtime (2026-09-27)

Text-180: 168/180 (93.33%) — GSM8K 98.75%, HumanEval 97.5%, IFEval 77.5%, hard_reasoning 95.0%. BFCL-hard20: 6/20. Full 200: 174/200 (87.0%). Serial execution, effort=low, zero transport errors. (The vLLM runtime's 2026-09-21 kit on its own 32K profile: 170/180 text, 10/20 BFCL — engines are independent; scores do not transfer.) Evidence: evidence/glm53-exl3-q200v2-20260927/ in the ExLlamaV3 runtime repo.

Known limits

• Single GB10, TP=1. Vision verified by image Q&A smoke (image requests are drafted text-only under DFlash2).
• C≥2 tool-call loads not exercised on the 256K profile.

Provenance

Quantized by r0b0tlab from zai-org/GLM-5.3-Flash (MIT). Weights unchanged beyond quantization. EXL3 format follows exllamav3 (MIT).