llama.cpp divides total -c across --parallel slots, so -c 4096 --parallel 4
gave each request only 1024 tokens — truncating long AIME generations before
the boxed answer and making xserv look artificially better (20% vs 3.3%).
Set total -c = max_seq_len * n_parallel so per-slot context equals xserv's
per-sequence max_seq_len. Also drop --log-disable; its startup log reports the
per-slot n_ctx that catches exactly this misconfiguration.
After the fix, AIME is at parity (xserv 23.3% vs llama.cpp 20.0%), matching the
GSM8K parity and confirming the gap was a config artifact, not engine quality.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Refinements from end-to-end bring-up on the GPU host:
- Run each system start→suites→stop in sequence. Two BF16 8B models don't
co-reside on one 32GB GPU, and a resident idle engine would distort the
other's latency/throughput.
- Match generation mode: xserv hardcodes Qwen3 thinking off, so send
chat_template_kwargs={enable_thinking:false} to llama.cpp via a per-endpoint
extra_body. --enable-thinking opts back into thinking mode.
- Add tools/__init__.py so `python3 -m tools.bench.runner` resolves our package
instead of a site-packages `tools` (nvfuser ships one that shadowed it).
- Document offline-GPU-host workflow, thinking-match, and the xserv 8192 OOM
finding that the bench surfaced.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Vendor llama.cpp as a submodule pinned to b9371 and add a one-click
benchmark driver that compares xserv against it on identical workloads:
- setup-llama-cpp.sh: network-optional CUDA build (SM120); convert-to-gguf.sh
converts the same safetensors to BF16 GGUF for an apples-to-apples baseline.
- tools/bench/: black-box OpenAI-API driver measuring TTFT/TPOT/throughput
(single-stream + concurrent) and response quality on AIME 2025 + GSM8K.
- fetch_datasets.py pulls datasets to local JSON (GPU host has no network);
task loaders prefer the local JSON.
- sync-and-build.sh: `bench` subcommand transfers source + datasets to the
GPU host via tar-over-ssh (no rsync there), builds, and runs the suite.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
- Cargo workspace with xserv-cuda crate
- CUDA FFI bindings (cudart: memory, stream, device, error)
- GpuBuffer RAII wrapper with H2D/D2H/D2D copy
- CudaStream wrapper with RAII Drop
- CachingAllocator with size-bucketed free lists
- PinnedBuffer for page-locked host memory
- Device info query via cudaDeviceGetAttribute
- Vector-add CUDA kernel smoke test
- Integration test suite (11 tests)
- build.rs: cc crate compiles .cu for SM 12.0
- sync-and-build.sh for remote build on dash5
- Roadmap doc (docs/00-roadmap.md) and Phase 0+1 design doc
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
