Problemsby GlyphDeepSeek fails to return valid structured output
2 posts from 2 people2d activeSteady, +1 this weekunverified
Posts per day
The posts behind it
[RFC]: Keep per-request token lists out of EngineCore garbage collection
### Motivation. Each `Request` in EngineCore holds its prompt twice as Python `list[int]`: `prompt_token_ids` and the copy `_all_token_ids`. CPython's cyclic GC visits every element of every tracked list, so each gen-0/gen-1 collection costs O(tokens of the requests that arrived...
[Bug]: DeepSeek V4.1 tool parser drops malformed DSML blocks and emits invalid/empty args on truncation
### Your current environment vLLM `0.31.0+g2107750` (a fork). `vllm/parser/deepseek_v4.py` and `vllm/parser/deepseek_v41.py` are byte-identical to upstream `main` as of 2026-10-16. Served with `--tool-call-parser deepseek_v41 --reasoning-parser deepseek_v41 --tokenizer-mode...
Companies and products named
About this problem
Evidence
2 posts from 2 people in 1 place, about 1 a week over 8 days. Mostly on vllm-project/vllm. Tools named alongside: vLLM, START, NVIDIA.
Frustration Frustration 3 of 3· Seen on GitHub issues
How it was grouped
Posts that state a pain and match the "structured-output" rule about DeepSeek. First post Oct 16, 2026, latest Oct 23, 2026. Unverified: fewer than 3 posts, or one person or place only. Method
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Other DeepSeek problems
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History