Every agent file on the cluster named its own node, its own address, the
path to llama-server and two weight directories — different on every node,
kept true by hand, and not true: node05 carried "ram: 32g" beside a measured
31 GB, looked for weights in an empty directory while fetching them into
another, and the other four never looked in theirs at all, so four nodes
reported no disk. Growing a node's RAM would have gone unnoticed, because
memory was read once, at registration.
The agent now finds these out. Its id is the hostname, which is also the
certificate's common name. Its address is the one on the route to the
control plane, which the kernel picks for a UDP dial without sending
anything. llama-server is looked for on PATH and then where release archives
are unpacked. A missing nvidia-smi is a node without NVIDIA cards rather
than a failed discovery — which also cut discovery short before InfiniBand
on every CPU node not told to skip GPUs. Fetched weights land in
/var/lib/llmgw-weights by default, and wherever they land is always looked
in.
Memory is read on every heartbeat, and installed engines are probed again
each minute and sent when they change, so a VM given more RAM or a node
given vLLM becomes a candidate without anyone restarting its agent. The
control plane logs both changes, since "the node now qualifies" is the
answer to why a model placed an hour after it was asked for.
What is written still wins. The agent file shrinks to the control plane's
addresses and the TLS files, the same on every node; onboarding writes only
the overrides it was given. What cannot be found stays configuration: which
fabric an adapter is on, because OpenSM's default prefix is the same on all
of them.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
The dashboard charted what the cluster had been billed for — requests, tokens,
spend, all from llmgw's own store — and nothing about whether it was healthy.
Saturation, queue depth, cache occupancy and replica counts were numbers in a
table at the instant the page loaded, with no way to see that one of them had
been climbing for an hour.
Four line charts now, read back from wherever the metrics were scraped to.
Read back rather than kept twice. llmgw publishes these already; what a gauge
cannot do is remember, and a ring buffer in this process would be a rival copy
of the same numbers with its own retention, lost on every restart and
disagreeing with the one an operator has on screen elsewhere. monitoring.prometheus
is empty by default and the panels are then absent rather than empty.
One axis per chart, always. Two measures of different scale belong in two
charts: a second y-axis lets any two lines be made to cross wherever the author
likes and the reader cannot tell it happened.
Four colours, handed out in fixed order, never cycled. A fifth series is summed
into "other" and drawn in grey — dropping it would make a chart that does not
add up, and inventing a hue for it would put two lines on the page that nobody
can tell apart. The fold is by timestamp, not by position: the tail's series do
not share sample times, and adding them by index slides points sideways onto
each other's clock.
A legend for every chart with more than one line, because colour alone is not
an encoding a reader can rely on.
A flat zero is drawn along the bottom rather than left blank: nothing happening
is a real answer, and an empty frame reads as a broken chart. A single sample
is not a line and says so instead of putting a dot in the corner.
One failed query fails all four panels. Three drawn and one blank invites
reading the blank one as "nothing is happening there".
NaN is dropped rather than plotted. Prometheus sends it as a string for a
sample it has no value for, Go's ParseFloat accepts it happily, and one NaN
coordinate is an SVG path that does not draw at all — taking the rest of the
line with it.
Axis maxima are rounded to a number a person would pick. An axis topping out at
0.8347 makes every gridline unreadable, and the shape is what a chart is for.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
A gateway serving nine models offered nine names and nothing to choose between
them. /v1/models is the only view most clients ever have, and it listed ids.
Models carry a description now: written when the model is added, shown on the
dashboard and sent to clients in /v1/models.
Written rather than derived. A registry offers a pipeline tag and a wall of
README, and neither answers the question somebody picking from a list is
asking — which of these should I send this request to. "General chat, strong
Swedish; slower than the 8B" is not in any metadata field.
It is optional, and absent means absent rather than an empty string in the
response: a model nobody described should read as undescribed, not as described
with nothing.
On the dashboard it sits under its row rather than in a column. A sentence in a
table cell either wraps every other column into a stripe or gets cut off.
Co-Authored-By: Claude Opus 5 (1M context) <moreply@anthropic.com>
Mirroring anything meant knowing a repository existed, knowing which of its
thirty files were the weights, and assembling a resolve URL by hand. The mirror
page had a text box for that URL and no way to find one.
It now searches Hugging Face and lists a repository's weight files with their
sizes and published checksums, each with a button that fills the fetch form.
Only weight files. A repository is mostly a README and a tokenizer, and listing
those buries the four entries somebody came for.
The size shown is the LFS size, not the plain one. For an LFS-stored file —
every weights file — the plain field is the size of the pointer, so the other
one reports a gigabyte model as 133 bytes, and that is the number somebody
would then plan disk against.
The source URL is pinned to the commit the listing came from rather than to a
branch, so what the mirror fetches is what was on screen. A repository
re-uploaded under the same branch otherwise leaves two different sets of
weights with identical provenance and no way to tell them apart. The version
defaults to that revision for the same reason.
The registry's own failures are reported on their own line. It is somebody
else's server on the other side of the internet, and it being down says nothing
about the mirror — which is what the page is for and has to keep working
regardless. With no registry configured there is no search box at all, rather
than one that can only time out.
Gating decodes from a bool or a string, because the field is documented as the
first and is the second in practice: strict decoding fails the whole response,
so one gated model would hide the other nineteen in a page of results.
And a bug this made obvious: downloads were keyed by model and version, so the
second shard of a sharded model was refused as "already fetching" until the
first had finished. A fifteen-shard model had to be pulled one file at a time,
each waiting on the last. Keyed by file now — which is what the single-flight
was ever protecting, since the race is two writers on one .part. A version made
of several files reports as the worst of them: it is not present until every
shard is, and one shard failing makes the version unusable however many others
arrived.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Control plane mode was inferred from the config file alone: a model with
profiles meant "control plane", nothing meant "router only". So a deployment
that manages its catalog at runtime could not start at all — the file declares
no models, the process refuses for want of anything to serve, and the stored
models it would have loaded are never read. A cluster unmanageable at runtime
because it is managed at runtime.
control.enabled says so outright. AgentListen cannot carry the signal: it has a
default, so every deployment would silently become a control plane.
The inference stays, so nothing already working has to add a flag.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
/admin/mirror, behind the same admin session as the other admin pages. What is
held, what is arriving with its byte count, what failed and why; start a fetch,
retry a failed one, remove a version.
Not mounted at all without a mirror configured. The right page for a deployment
with no mirror is no page, rather than an empty one pointing at nothing.
It reloads itself only while something is downloading. A reload at any other
moment takes with it whatever is half-typed into the fetch form, and there is
nothing to watch when nothing is moving.
A failed row offers Retry, not Remove. A fetch that failed left nothing on disk,
so the remove could only answer "the mirror holds nothing for this" — a button
whose single outcome is a confusing error. Starting the same download again is
what somebody looking at that row wants, and the mirror allows it: only a
download still running is refused.
An unreachable mirror is said outright instead of rendering as an empty table.
The two look nearly identical and mean opposite things: one is a mirror waiting
to be filled, the other is a machine to go and look at.
Dashboard takes NavExtras rather than a second bool. Two adjacent booleans at a
call site get swapped silently and are discovered by somebody clicking the
wrong link.
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>
