"Set up a local mirror" was advice. This is the nginx config, the directory
layout and the reason the layout has a date in it — a repository that changes
upstream changes what you are running, and the first sign is a prompt that
worked last week answering differently this week.
It says what the mirror is not, because both mistakes are easy. It is not a
caching proxy: nothing populates it on demand, deliberately, since a mirror
that reaches the internet at the least convenient moment fails in a way that
looks like llmgw being broken. And it is not needed at all if you already run
a shared filesystem — put the models there, use a path, and nothing is fetched.
It also says when a mirror stops being enough, and that llmgw is positioned to
distribute between nodes because it already knows which of them hold which
weights. That is not built, and the page says so rather than implying it is
coming.
Every behaviour it relies on was checked against the source: an http:// source
is fetched and a path is not, a killed download resumes, a partial file is
never visible under the model's name, and a shared filesystem is not counted
once per node.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Neither had a page. "We have GPUs, now what" was left to the reader, and what
llmgw stores was scattered across four documents and a changelog — which is
the same as not being written down when somebody is doing a security review.
docs/data.md describes the behaviour and leaves the legal mapping to whoever
holds the obligation. Every claim in it was checked against the source, and it
names where to look for each: usage rows carry no text field, keys are stored
hashed, conversations are off until a named project turns them on and cannot be
turned on without a retention window.
It also states the egress exactly, which took reading every outbound call to
say honestly: nothing on the serving path leaves the cluster, and the two
things that can reach outside — fetching weights, and ctl plan reading a model's
architecture — are both started by an operator. Weight fetching points wherever
you tell it, including an internal mirror.
docs/choosing-models.md is the opinion llmgw itself does not have. Three jobs
rather than one model, with the third — embeddings — being the one that gets
forgotten and the one that decides whether the deployment can answer questions
about your company or only questions in general.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The last piece of HA, and it is a deployment pattern rather than code: llmgw
picks one leader and agents follow it, but client traffic arrives in front of
both and llmgw is not in front of anything.
Writing the pattern found a bug in the pattern. The first draft said to
health-check `/health` and claimed a standby still routes to replicas the
leader placed, so sending it traffic was fine. It does not. A standby's
reconciler places nothing and it holds no agent streams to adopt from, so it
publishes an empty endpoint list — a load balancer following that advice would
have sent half the traffic to something that answers every request with 503.
So there is now a `/ready` that means "this process has somewhere to send a
request": 503 on a standby, 503 on a leader whose replicas have all failed,
200 when there is something to serve. `/health` keeps meaning the process is
up, which is a different and less useful question. Both are open, because a
load balancer has no key.
There is a gap during failover where neither passes — three seconds when the
leader stops cleanly, up to the lease TTL when it does not — and the document
says so rather than implying otherwise. Traffic cannot go to a control plane
that has nothing to route to.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
There was no reference. Four narrative documents explain how to install and
operate llmgw, and the only way to learn that `lease_ttl` exists was to read
the one that happened to mention it — or the struct.
Written by hand it would have been wrong within a fortnight. Six settings
arrived in the last two weeks alone: store, servers, lease_ttl, the two
retention windows, min_disk_gb. A reference nobody maintains is worse than
none, because it is the same list with the setting you came to look up quietly
missing from it.
So it is derived from the structs, with the field comments as the descriptions
— which means the only way for it to be wrong is for the code to be wrong, and
it makes the comments worth writing twice over. 1163 lines, 24 blocks, 87 keys.
Two tests keep that true after everyone has forgotten this exists. One
regenerates and compares, so adding a setting without regenerating is a
failure rather than an omission — checked by adding one and watching it fail.
The other walks the tree for koanf tags and fails on a configuration file
that is in neither the source list nor the short list of structs an operator
never writes, because a list is a thing to forget.
The generator finds the repository from its own path rather than the working
directory, so `go generate ./...` produces the same document from anywhere.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The store stops being a file on one machine, which is what stood between this
and more than one control plane.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Seventeen commits since v0.6.0, and not a phase of the roadmap — which is why
the table leaves the phase column empty rather than inventing one. What landed
is what a cluster needs to be lived with rather than demonstrated: somewhere
to keep a conversation, somewhere to keep a note, and an honest answer about
the disk underneath both.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Two of the four items were already built. A model falls through to its
fallbacks on no capacity as well as on a spent budget, and the per-request
routing profile header exists — it is ignored under authentication on purpose,
because a header that picks a routing profile is a header that promotes a
client into the top priority band.
Checked against the code rather than against memory, which is how both got
onto the list in the first place.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The changelog had two "Unreleased" headings. The second sat below v0.5.0 and
was the detail behind it — phases 2 and 3, written while they were in progress
and never folded in when the release was cut — so it claimed as unreleased
work that had been shipped for two days. It is now a section of v0.5.0. The
status table said v0.5.0 was planned, which its own release notes disprove.
The first "Unreleased" becomes v0.6.0: eighty commits, of which phase 4 is the
headline and the rest is what a cluster needs before anyone but its operator
is let near it.
Two things would have stopped the release workflow publishing anything:
Gitea gives every job a built-in GITEA_TOKEN, but what it may do depends on
the instance's default mode, and under the restricted default it is read-only
on releases. The job now asks for `releases: write`, which is correct under
either default. An upload that is refused now fails the job — without `-f`,
curl treats a 403 body as a successful transfer, so the release would end up
with some of its files, or none, and a green tick either way.
`workflow_dispatch` is offered but the upload assumed a tag. Fired from a
branch it would have created a release named "main".
README's status paragraph still said authentication, budgets and the control
plane were missing. It now says what is actually left, including the part
worth saying out loud: the InfiniBand, NVML and NCCL paths have never run on
a machine that has any of them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Written for whoever is standing up the cluster with root on some servers and
nothing installed. Control plane, certificate authority, first node, first
model, first request.
It leads with what llmgw does not install — drivers, CUDA, engines, weights
— because a node missing any of them registers, reports ready, and fails
every replica placed on it, and the reason is three logs away. The useful
order is to make a node able to serve before onboarding it, which is the
opposite of what the tooling's convenience suggests.
The failures it warns about are ones this cluster actually hit: llama-server
present and unable to start for want of libgomp1 while the node reported
healthy; a Proxmox VM on the default kvm64 CPU, where inference is six to
nine times slower and nothing looks broken because every number is simply
small; requests dying at exactly sixty seconds on a liveness timeout that is
a generation budget in disguise for non-streaming calls.
Verified rather than recalled. Every command it prints was checked against
the binary, every config key against the struct tags, and its own
verification and troubleshooting commands were run against the live cluster.
That caught two errors in my draft: the health endpoint is /health and
returns an empty body, not /healthz, and the Go version needed is 1.26.
The known-gaps section is there so a reader finds them on a Tuesday
afternoon rather than at 2am: weights and engines are theirs to distribute,
there is one control plane and no HA, and multi-node replicas have never run
on real InfiniBand — only against simulated hardware.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
ctl talks to a management API on the admin listener, not the client-facing one.
The two have different audiences: one serves inference to whoever holds an API
key, the other lets a caller cordon nodes and read the cluster's shape.
- nodes surfaces unhealthy GPUs and why they are excluded. That is usually the
answer when a node looks idle but nothing will schedule onto it, and it was
invisible before.
- explain-placement prints every candidate considered and why it was rejected.
- replicas shows the shards a replica is made of, with per-shard errors.
- cordon, uncordon and drain are one endpoint with different targets, because
the difference between cordon and drain is exactly what an operator needs to
be sure of before running either.
Draining had to be fixed first to make ctl drain worth having. A drained replica
was stopped on the next pass, which cuts in-flight requests — the thing draining
exists to avoid. Now a node marked Draining has its replicas drained, the model
falls below its desired count, a replacement is placed elsewhere, and the
original is stopped only once the replacement is serving. A grace period bounds
it, because draining the only node that can host a model would otherwise never
finish and the node could never be taken out of service.
Verified against a two-node cluster of real binaries: draining moved a replica
to the surviving node and traffic kept returning 200 throughout.
ctl logs is deliberately absent. It needs a request/response pair the agent
protocol does not have, and the failure path already ships an engine log tail
with every status report — so the case that matters most is covered, and
reading a healthy shard's output on demand is not worth a protocol change yet.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Inserted between quota checks and scheduling: admission answers when a request
may proceed, the scheduler still answers where it goes. Keeping them apart is
the point — an engine queue is FIFO and knows nothing about tenants, so once a
batch job is in it, no endpoint selection rescues the request behind it.
- saturation detector: one number per pool, the worse of queue depth and KV
occupancy, since either alone misleads.
- priority bands with per-band saturation ceilings, so the cluster degrades from
the bottom up.
- tenant round-robin within a band: one caller sending a thousand requests takes
one slot in the rotation, not a thousand.
- bounded queues with capacity (503) and TTL (504); cancelled requests leave the
queue instead of holding capacity.
- metrics for queue depth, wait time, rejections and pool saturation.
Exit criterion, measured in test/e2e: with 500 concurrent bronze requests
running continuously, interactive p99 in the platinum band stays at 1.04-1.24x
idle against a 1.5x budget. With admission off the same load pushes it to
55-60x. Both directions are asserted, so the test fails if admission regresses
and also if the load generator stops being a real load.
Two lags had to be closed, and they needed different answers. Engine metrics are
scraped and lag an interval; router inflight does not, but it counts running
requests, and treating those as queue makes a healthy engine look overloaded
every interval. What is actually queued is inflight minus batch capacity, and
capacity is not in the metric contract, so it is learned as the high-water mark
of observed running. Separately, between admission granting a request and the
router dispatching it the request is invisible everywhere, so a simultaneous
burst passed the check en masse; the controller now counts its own outstanding
leases against dispatched inflight.
One plan correction: a saturation ceiling of 1.0 was documented as "never held
back". It is not — it means "flow up to the healthy limit". A band that must
never wait needs a ceiling above 1. Plan §7.2.2 updated.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
llmgw server is real now. It fronts a static set of engine replicas with an
OpenAI-compatible API, scoring endpoints through the pipeline added in the
previous commit.
- proxy: SSE relayed event by event with a flush after each, cancellation
propagated upstream, and separate deadlines for dial, headers, first token,
inter-token idle and total. The idle watchdog is what distinguishes a wedged
engine from a slow one.
- router: dispatch with retry and model fallback. Retry only happens while
nothing has reached the client; after that, splicing two responses together
would be worse than the short stream the client already sees.
- config: YAML via koanf overlaid on defaults, with LLMGW_ env overrides.
Validation rejects duplicate endpoint ids and aliases that shadow a model,
because both misroute silently at request time rather than failing loudly.
- metrics: requests, duration, TTFT, tokens, plus per-scorer values and
per-filter drops on a separate admin listener with health and pprof.
Phase 1 exit criterion, measured in test/e2e: 1000 concurrent streams across
3 sim-engines complete at ~6800 req/s; every client disconnect frees the KV
blocks on every engine; router overhead p99 is about 0.9 ms against the plan's
2 ms budget.
The handlers live in internal/router rather than an internal/router/openai
package as the plan's tree sketched: they need the dispatch loop, and splitting
them apart would have meant an interface with exactly one implementation. Plan
§4 updated to match.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Versions track the phases in the plan: a phase is released once its exit
criterion is met, not when its code lands. That keeps "released" meaning
something — v0.1.0 ships sim-engine and the routing libraries, and says plainly
that the gateway does not serve traffic yet.
scripts/gitea/milestones.py creates the matching Gitea milestones. Idempotent
and never destructive, so it can be re-run after the roadmap shifts.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Comments, doc comments, test names, error and log messages, CLI help, README,
Makefile, CI step names and the design document are now all in English.
No behaviour changes; the full suite passes under the race detector.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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