Tests. First automated coverage for the project: 164 tests, 2.7s, no GPU or network.
An autouse fixture stubs overclock_manager._sh -- the single choke point for every
nvidia-smi/nvidia-settings write -- so no test can mutate the card. They deliberately
pin the empirically measured constants that would otherwise rot silently: the cold and
warm load figures behind the cache-hit thresholds, the warm_confident residency rule,
and the busy/stalled yield split. One test asserts RAM_HIT_GBPS stays at or below the
measured 2.63 GB/s warm load, so the old physically unreachable 5.0 GB/s bar cannot
come back.
Three bugs the suite surfaced, now fixed:
- autotune._subsample(values, 1) divided by zero; the early return only covered
len(values) <= max_steps.
- telemetry_store.stop() flushed its local pending list but never drained the queue,
silently losing rows submitted just before a shutdown -- exactly when the last
events matter.
- ram_optimizer.page_residency's zero-byte short-circuit omitted keys every other
return path provides, so a 0-byte file was planned for warming.
Reclaim. The README has claimed bidirectional arbitration from the start, but only one
direction was ever automatic. Establishing what actually happens took a controlled test
with the service stopped: with ComfyUI holding 6.83 GB, Ollama does not spill to the CPU
on this box -- it aborts with "cudaMalloc failed: out of memory", because n_gpu_layers is
pinned to 99 and it will not reduce the layer count. So both failure modes are handled:
_check_ollama_starved watches size_vram < size for the default configuration where Ollama
does spill, and switch_ollama_model catches the hard OOM, reclaims VRAM from an idle
ComfyUI and retries once. The request that returned HTTP 500 from Ollama directly now
succeeds through HyperSwap, loading at 3.85 GB/s after reclaiming 6.83 GB.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Nine changes, in rough order of how much they affect real behaviour:
1. VRAM yield is now a barrier. Posting keep_alive:0 only asks Ollama to unload;
measured here, the HTTP call returns in 63ms while the driver takes a further
77ms to release 14.9GB. Returning inside that window is how ComfyUI ends up
allocating into VRAM that is still occupied. instant_free_ollama_vram() polls
NVML until the allocation is actually gone and reports request/confirm split.
2. ComfyUI VRAM is no longer purged 1.5s after every prompt, which forced a full
checkpoint reload on each workflow iteration. It is held for 30s of genuinely
empty queue, with an immediate purge when Ollama actually asks for the memory.
3. Cache-hit classification uses achieved bandwidth (size / load duration) rather
than a fixed `load_duration < 2500ms`. That constant called a 12.9GB model read
at 2.9GB/s a cold load, and a 0.5GB model read from NVMe a cache hit.
4. Page-cache residency is measured, not assumed. mincore(2) reported 128GB
resident on a box with 46GB of page cache: the kernel only permits page-cache
introspection on files you own, and the Ollama blobs are owned by uid ollama,
for which mincore answers "all resident" instead of failing. Uses cachestat(2)
where permitted and a randomised read-rate probe elsewhere, labelling which was
used. Fixed-offset probing was self-fulfilling, so windows are random and cold
ones are returned with FADV_DONTNEED.
5. Warming is budgeted and ranked by recency/frequency instead of reading every
file top-to-bottom, which on 64GB of RAM just evicts whatever was warmed first.
6. Telemetry and events persist to SQLite (~0.38 MB/hour) instead of living in a
50-entry in-memory deque, so /api/analytics/profiles can finally answer whether
an overclock profile actually delivers more tok/s.
7. Thermal governor walks the overclock back on sustained heat or hardware
throttling, with hysteresis, fed from the existing sampler.
8. Autotune sweeps a clock offset, benchmarks decode at each step, watches for Xid
errors and degenerate output, and restores the profile in a finally block.
9. Stock clocks/power/fans are restored on shutdown and via systemd ExecStopPost.
Nothing previously undid a locked clock or a manually pinned fan.
Also: one shared 1Hz telemetry sampler fanned out to SSE subscribers rather than
every client re-running the whole snapshot; wall-clock timestamps in place of the
event loop's monotonic clock; cached nvidia-smi shell-outs; quieter httpx logging.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
