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[BUG] Ternary Bonsai 27B enters infinite prompt-processing loop, never generates response — context grows unbounded (43k+ tokens), session 8h+ #77

Description

@Milor123

I'm reporting what appears to be a critical bug in the llama.cpp serving path for Ternary Bonsai 27B, not a performance complaint.

System

  • OS: Windows 11 25H2
  • GPU: RTX 4070 12 GB
  • CPU: Intel i5-14500, 48 GB RAM
  • Build: PrismML-Eng/llama.cpp, compiled from source today
  • Model: Ternary-Bonsai-27B-Q2_0.gguf
  • Vision: Ternary-Bonsai-27B-mmproj-BF16.gguf
  • Client tested: Hermes Desktop and OpenCode — same behavior in both

llama-prism-b1-62061f9-bin-win-cuda-12.4-x64

llama-prism-b1-62061f9-bin-win-cuda-12.4-x64  .\llama-server.exe -m "C:\Users\User\.vllm\Ternary-Bonsai-27B-dspark\Ternary-Bonsai-27B-Q2_0.gguf" --host 127.0.0.1 --port 10000 -ngl 99 -c 106000 -b 8192 -ub 2048 --temp 0.7 -np 1 --top-k 20 --top-p 0.95 --api-key JORCH_SK_d736nng1mX4OFza5uFcbDfcVmVXKqjQOPV7gTXNIB47LhPD0hXddZKl8sPtsAlszjLZ --cont-batching --metrics -ctk q5_0 -ctv q4_0 --jinja -tb 20 -t 20 --dry-multiplier 0.8 --dry-base 1.75 --dry-allowed-length 2 --no-mmap --mmproj "C:\Users\User\.vllm\Ternary-Bonsai-27B-dspark\Ternary-Bonsai-27B-mmproj-BF16.gguf" -fa on

The bug

When given a task that triggers tool use / skill loading (in my case: "load the research skill and do extensive research on tallow consumption and benefits"), the model enters a state where prompt processing never terminates, the context grows without bound, and no response is ever generated.

Evidence from my session (screenshot attached)

Image

Console logs show prompt processing repeating with increasing token counts and degrading speed:

prompt processing, n_tokens = 8192,  progress = 0.19, t = 270.64 s  / 30.27 tokens per second
prompt processing, n_tokens = 16384, progress = 0.38, t = 1004.23 s / 16.31 tokens per second
prompt processing, n_tokens = 24576, progress = 0.57, t = 2266.99 s / 10.84 tokens per second

Meanwhile the UI shows the context growing: 43.2k / 106.2k tokens consumed.

Session timer: 8 hours 26 minutes and still running. The model has never output a single token of response or thinking.

Why this is not "slow inference"

  • Not a thinking delay: If this were the model's <think> block, tokens would appear in the output. Nothing appears.
  • Not a tool loop: The client shows no tool calls being made. The server is stuck in prompt processing.
  • Context explosion: The token count grows from 8k → 16k → 24k → 43k+ without user input. This suggests the server is repeatedly re-processing an ever-growing internal state.
  • Degrading throughput: Speed drops from 30 t/s → 16 t/s → 10 t/s as the context bloats, confirming the work is real and unbounded, not a deadlock.

What I expected

The model should either:

  1. Generate a response (including thinking tags), or
  2. Fail with a clear error, or
  3. Timeout — not spin for 8+ hours consuming CPU/GPU and growing context.

What actually happens

Silent, infinite prompt processing with unbounded context growth. The only way to stop it is killing the server.

Additional context

  • reasoning-budget: activated, budget=2147483647 tokens appears in logs (unlimited thinking budget).
  • --cont-batching is enabled.
  • -c 106000 configured.

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