frank-default-small: ncmoe 32 + ubatch 1024 from llama-bench sweep

Swept ncmoe(30..40) x ubatch(256..4096) on the RTX 3090 (Qwen3.6-35B-A3B
Q6_K_P, pp16384/tg512, fit-target 0). Key findings:
- Generation depends only on ncmoe: 40.9 (ncmoe40) .. 51.1 (ncmoe30);
  ubatch/batch do not affect decode at all.
- Prefill + graph VRAM scale with ubatch; logical batch is irrelevant.
- VRAM model (peak + 11.44GiB KV pool + 2.2GiB overhead) reproduces the
  historical OOMs: ncmoe32-ub2048 sums ~24.4GiB > 24.

Chosen state: ncmoe 32 (8 expert layers on GPU), batch 8192, ubatch 1024.
  gen ~48.7 t/s (+7% vs prior ncmoe 35), prefill ~766 t/s, ~1.0GiB headroom.
Alternates: ncmoe34-ub2048 (gen 46.4, pp 1221, 1.5GiB) for prefill-heavy;
  ncmoe32-ub768 (1.3GiB) if headroom matters most.
Docs: new frank-default-small-benchmark.md; synced deployment.md + specs.
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@@ -51,11 +51,11 @@ Dankserver is an NVIDIA GPU server for vLLM inference. The host runs Ubuntu 24.0
### Active Services
The active `frank-default-small` service (llama.cpp, `b10108+`) serves the HauhauCS Qwen3.6-35B-A3B uncensored `Q6_K_P` model on port 7770 with **ngram-mod** speculative decoding. It runs **4 parallel slots** at 200000 context each (pool 800000). Of the 40 layers' MoE expert weights, **35 sit on CPU** (`--n-cpu-moe 35`) while the remaining **5 layers' expert weights** are resident on GPU along with all non-expert tensors (`--gpu-layers all`). KV stays on GPU with K=`q8_0`, V=`f16`. Batch 8192 / ubatch 2048, `--ctx-checkpoints 4`, `--no-mmap`. At idle ~22.2 GB VRAM used, leaving an estimated **~1.8 GiB** headroom (up from ~870 MiB at `--n-cpu-moe 32`). Idle RAM ~32 GB of 62 GB.
The active `frank-default-small` service (llama.cpp, `b10108+`) serves the HauhauCS Qwen3.6-35B-A3B uncensored `Q6_K_P` model on port 7770 with **ngram-mod** speculative decoding. It runs **4 parallel slots** at 200000 context each (pool 800000). Of the 40 layers' MoE expert weights, **32 sit on CPU** (`--n-cpu-moe 32`) while the remaining **8 layers' expert weights** are resident on GPU along with all non-expert tensors (`--gpu-layers all`). KV stays on GPU with K=`q8_0`, V=`f16`. Batch 8192 / ubatch 1024, `--ctx-checkpoints 4`, `--no-mmap`. At idle ~23.0 GB VRAM used, leaving an estimated **~1.0 GiB** headroom (chosen by benchmark, see [[frank-default-small-benchmark]]). Idle RAM ~32 GB of 62 GB.
## Hardware Relevance
- 24 GB VRAM is close to saturated with this config. At idle ~22.2 GB used, leaving an estimated **~1.8 GiB** headroom at `--n-cpu-moe 35` (5 layers' experts on GPU). The move from `--n-cpu-moe 32` to 35 traded a little GPU-expert speed for OOM safety after high-load sessions OOM'd at 32 and 33. If headroom proves too thin for production bursts, dial back `--n-cpu-moe` to 37 (only 3 layers on GPU, ~0.9 GiB more headroom) by editing `scripts/frank-default-small.env`.
- 24 GB VRAM is close to saturated with this config. At idle ~23.0 GB used, leaving an estimated **~1.0 GiB** headroom at `--n-cpu-moe 32` (8 layers' experts on GPU) with `ubatch 1024`. A llama-bench sweep ([[frank-default-small-benchmark]]) chose this state: it maximises decode (~48.7 t/s) while staying above the OOM boundary that `ncmoe 32 - ubatch 2048` crossed (24.4 GiB). If headroom proves too thin for production bursts, reduce `ubatch` to 768 (~1.3 GiB headroom) or dial `--n-cpu-moe` back to 34 at `ubatch 1536` (~2.0 GiB headroom) by editing `scripts/frank-default-small.env`.
- 62 GB system RAM holds the ~29 GB of MoE expert weights with room to spare (~57 GB available after load).
- 127 GB swap is available for CPU KV cache paging if GPU KV offload is disabled.
- Root disk has approximately 140 GB free. Store the GGUF models under `/home/dank/models` (about 32 GB total).