Commit Graph
39 Commits
Author SHA1 Message Date
Ilker ManapandClaude Opus 5.5 bf2d171e89 Read NVLink and GPU-to-adapter distance from nvidia-smi topo
The release binary is built without cgo, so without NVML, and NVML was
the only source of NVLink peers: on every NVLink machine the portable
agent reported none, and tensor-parallel groups were chosen by GPU index.
Discovery now reads `nvidia-smi topo -m` after either path, for the
NVLink peers (kept from NVML where it gave them), each card's NUMA node,
and how far each network adapter is from it - PIX, PXB, PHB, NODE or
SYS - which travels to the control plane as nic_paths for placement to
use. Both the NICn-with-legend layout of newer drivers and the
adapter-named columns of older ones are read.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-29 00:09:26 +02:00
Ilker ManapandClaude Opus 5.5 daed835d88 Measure each node's CPU and memory, and give every node a page
The nodes are CPU machines, and nothing measured how busy one was: the
heartbeat carried GPU memory and disk, and llmgw_node_memory_bytes is the
total. The agent now reads /proc between heartbeats - CPU across all
cores, load averages, memory used and available, and each engine's
process group's cores and resident memory - and sends it with the
heartbeat. Nothing new runs on the nodes and Prometheus needs no new
target: the control plane exports it with the rest of the fleet, as
llmgw_node_cpu_utilization_percent, llmgw_node_cpus, llmgw_node_load,
llmgw_node_memory_used_bytes, llmgw_node_memory_available_bytes,
llmgw_shard_cpu_cores and llmgw_shard_memory_bytes. A measurement more
than a minute old is left out rather than repeated.

The cluster page's node table shows CPU and RAM as bars, and each node
links to a page of its own: current CPU, RAM, load and disk, the engines
on it with their cores and memory, and an hour of CPU, RAM, load,
per-model cores and memory and queue depth from Prometheus. It refreshes
in place.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 23:21:23 +02:00
Ilker ManapandClaude Opus 5.5 cba65f5be7 Move a control plane to PostgreSQL with server init --postgres
Installs PostgreSQL with the machine's own package manager when it has
none (initdb with password auth on the RHEL family, whose default is
ident), creates the llmgw role and database with a generated password
kept in /etc/llmgw/secrets/store-dsn, and checks the address connects.
On a machine already on SQLite it stops the gateway, copies the store
so accounts and keys survive, points auth.store at the new address and
starts it again. A move that fails starts the gateway on SQLite again.

server.yaml is edited as text so its comments survive, and kept beside
it. A PostgreSQL init did not install is not resized: it may serve
something else. It refuses to move one PostgreSQL store into another.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 14:33:03 +02:00
Ilker ManapandClaude Opus 5.5 33e678ab84 Show a node's logs on the admin page
Seeing what a node did meant ssh through a jump host, to a machine whose
address nobody remembers, to read a journal only root may open. When an
engine install failed on a new node today, the reason was one line — and it
was four steps away from the page that said the install had failed.

Each node's row on the cluster page now links to its logs: the agent's own,
and every engine running there, chosen from the list the node itself sends.
The page can follow, refreshing every five seconds, and is on both the admin
listener and /admin. `llmgw ctl logs NODE [--source SHARD] [-n N]` reads the
same.

They travel over the stream the agent already holds, so they need nothing
the control plane does not already have: a request goes down, the lines come
back, and a reply that does not come in ten seconds is an agent too old to
answer. The agent keeps its last 2000 lines in memory as well as writing them
wherever it did before; the engines' last few hundred lines were already kept
and sent only when one crashed.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 12:27:47 +02:00
Ilker ManapandClaude Opus 5.5 a40fc53e09 Wait for a new machine's own apt, and retry a failed install sooner
Found by building a node from nothing. Its agent tried to install libgomp1
while cloud-init and unattended-upgrades were running apt, and failed with
"Unable to lock directory /var/lib/apt/lists/": DPkg::Lock::Timeout covers
dpkg's lock, not the one `apt-get update` takes on its lists. The node was
correctly kept out of placement and said why, and then sat idle for the ten
minutes until the next pass.

A package command that fails only on a held lock is now retried for up to
ten minutes, reported as "waiting for another apt-get to finish" rather than
as a failure. A pass that does fail is retried after a minute, backing off to
ten.

The weights directory is created when the agent starts rather than by the
first download, so a new node reports its disk from its first heartbeat.

Onboarding takes several control plane addresses, comma separated, so a new
node gets the same failover list as the rest.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 12:14:22 +02:00
Ilker ManapandClaude Opus 5.5 f5d6210b86 Install engines on any glibc system, with its own package manager
The llama.cpp build is published from Ubuntu but is not Ubuntu's in any way
that matters: it needs glibc 2.34 and GCC 12's libstdc++, which Debian 12
and RHEL 10 have and RHEL 9 does not. Refusing every system not called
"ubuntu" turned away the first two for their name. The build is now tried
everywhere, and ldd decides.

What ldd says is made readable. "/lib64/libstdc++.so.6: version
`GLIBCXX_3.4.30' not found" is a system too old for the build, and is
reported as "libstdc++.so.6 is too old (needs GLIBCXX_3.4.30)", once —
rather than as a missing library that is plainly installed.

Packages are named per family — libgomp1 for Debian's, libgomp for Red
Hat's — and installed with whichever of apt-get, dnf, yum or zypper the
machine has, decided from ID_LIKE rather than a list of distribution names.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 11:10:06 +02:00
Ilker ManapandClaude Opus 5.5 7d97c6b74f Install a node's engines on the node, instead of trusting what is there
A node ran whatever llama-server somebody had once unpacked on it. Onboarding
checked an engine only when told its path, installed none, and a node with
nothing on it registered as ready. The one time that went wrong it went wrong
invisibly: the binary was there, executable, and could not start for want of
libgomp1, while the node reported healthy.

The control plane now says which engines every node has, at which version —
`engines:` in server.yaml, defaulting to the llama.cpp build this release was
checked against — and each agent converges on it. What only the node can
know, the node works out: the build for its processor and driver (CUDA with
its runtime when an NVIDIA driver is loaded, CPU otherwise), the OS packages
that build needs from its own package sources, and whether the result runs.
Every archive is checked against the sha256 GitHub publishes for it and
unpacked refusing any path or link that leaves the install directory. ldd
names a missing library outright; running `--version` proves the rest. Only
then is a directory marked installed, and it is checked again every ten
minutes, because an unrelated upgrade can remove a library.

An engine is reported only once installed and seen to run, or when the
agent's configuration names it on purpose — never because something happened
to be on PATH. The agent now says when it has probed, so an empty list means
"has none" rather than "too old to say": a node rebuilt from nothing is no
longer a candidate for every model at the moment it can run none of them.
Placement's refusal carries the node's own words, "installing: downloading
llama-b10991-bin-ubuntu-x64.tar.gz (16 MB)", and so do `ctl nodes` and the
cluster page, along with a warning for a CPU without AVX2 — the VM CPU type
that makes everything five times slower and nothing look wrong.

Agents also report their OS, architecture, vector extensions and NVIDIA
driver. Onboarding installs llmgw itself from the CI release for the node's
architecture, checked against the release's checksums, rather than copying
whatever binary the operator's machine had.

vLLM and SGLang are not installed yet: they are Python environments of
several gigabytes, not an archive, and still have to be named in the agent's
configuration.

Also fixes a race on the weights fingerprint, which two heartbeat loops touch
during a failover.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 10:59:59 +02:00
Ilker ManapandClaude Opus 5.5 20deb22dfa Let a node describe itself instead of being described by hand
CI / test (push) Successful in 1m47s
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>
2026-09-28 10:13:42 +02:00
Ilker ManapandClaude Opus 5 03e38e7dda Carry the profile fingerprint to the agent and back
CI / test (push) Successful in 1m39s
The stale-profile flag could not fire where it matters. The control plane
keeps no record of a running replica across its own restart — it rebuilds
them from what the agents report — and adoption left the fingerprint empty,
so every replica read as unknown afterwards. That is precisely the moment
the catalog is most likely to have been edited: change the configuration,
restart the server, and nothing would ever say the fleet disagrees with it.

The fingerprint now travels with StartShard, the agent keeps it beside the
pool and fabric it already echoes back, and adoption takes the replica's
version from the agent rather than from the catalog it is about to be
compared against. An agent too old to report it sends nothing, which still
reads as unknown rather than as matching.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-27 23:22:44 +02:00
Ilker ManapandClaude Opus 5 dfbb7557dd Serve a model made of several files
CI / test (push) Successful in 1m42s
The mirror would happily hold a four-shard model that nothing could serve. A
catalog entry names one source, the agent fetched one URL, and so a version of
several files had no way to be described — which is every safetensors model,
and every GGUF too large to ship whole.

A source ending in a slash names a version rather than a file. The agent fetches
every file in it into one directory and hands the engine the directory: vLLM
reads the shards and the config out of the folder, and llama.cpp is given the
first part and finds the rest beside it.

The trailing slash is the whole signal. A flag beside the source would be a
second place for the two to disagree, and a URL already distinguishes a
directory from a file everywhere else.

The mirror answers a version with a manifest instead of a file listing. A plain
file server gives HTML there, and something that has to know what a version
consists of would be left parsing it. It is on the byte listener, not the
management API: fetching weights is the one thing every node does, and making
it depend on the administrative port would undo the split that keeps that port
closeable.

Built from the directory rather than a file written beside it. A manifest on
disk is a second record of what is there, and the two disagree the first time
somebody copies a file in by hand — which the mirror explicitly allows.

The whole set or nothing. A directory with three of four shards loads as a
broken model rather than failing to load, so a completion marker is written
last and an interrupted fetch starts the missing files again rather than being
found and served. Files already there at the right size are not fetched twice.

Progress is reported under the version's address, not each file's: the shards
waiting on it asked for the version, and progress under a file's own URL
reaches nobody.

A filename from the manifest is refused if it contains a separator. The mirror
is a place an operator copies files into by hand, so what it reports is not
automatically safe to join onto a path.

An HTML listing where a manifest was expected says so. "invalid character '<'"
sends somebody looking at the wrong thing.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-27 21:07:26 +02:00
Ilker ManapandClaude Opus 5 2acd794022 Stop placing engines on nodes that do not have them
CI / test (push) Successful in 1m42s
A node's registry holds an adapter for every engine whether or not its binary
exists, the agent never said which were installed, and placement carried an
Engine field it had never once read. So a vLLM replica was as happily placed on
a node with no vLLM: the node registered healthy, the shard failed minutes
later with "executable file not found" in the engine's own words, and the
reconciler tried again.

That is how fifteen gigabytes of safetensors reached this cluster's mirror
before anybody noticed it had no card and no vLLM to run them with.

Agents now probe what is installed and report it — the protocol has carried
engine_versions since it was written and nothing ever filled it in. Placement
filters on the key set, `ctl nodes` has a column, and the mirror page's serve
warning is a fact instead of a guess about cards, which would have waved
through a fleet of eight-GPU nodes that never had vLLM.

Probing resolves binaries and runs none of them. The first version asked each
engine for --version, which is fine for an engine and not fine for the wrapper
scripts people put in front of one: a script that shifts past flags it does not
recognise and then execs the server will start an inference server, at agent
startup, on every node. The agent's own test suite installs exactly such a
script and caught it. So presence is a path lookup, and the version is left to
`ctl engine-check`, which is run by somebody who meant to run the engine.

SGLang is the exception and has to execute, because a module has no path to
look up — but the command is llmgw's own one-line import rather than the
engine's launcher. Its exit code is the answer: python3 is on almost every
machine, and treating a failed import as "installed" reported SGLang on every
node in a fleet that had none, which is the failure being fixed, inverted.

Probed once, not per reconnect, and bounded by the context that registration
waits on: an agent that cannot reach the control plane is worse than one
reporting an incomplete list.

A node that reports no engines at all is not excluded anywhere — by placement,
or by the page. That is what every agent older than this reports, and emptying
a fleet on a control plane upgrade is a worse failure than the one being fixed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-27 16:11:55 +02:00
Ilker ManapandClaude Opus 5 dde2bcab19 Stop asserting an ordering the supervisor does not promise
The test started a sidecar and an engine, each a shell appending its name to a
file, and demanded the sidecar's line come first. The supervisor spawns the
sidecar first, but spawning is not sequencing: without WaitForLeaderPort
nothing holds the engine back, so two shells race and the scheduler picks the
winner. It failed under full-suite load, and lately on its own.

The wait that is a real guarantee already has its own test, so the fix is to
check what this one is actually for — that both processes run under one shard,
that the shard's pid is the engine's rather than the sidecar's, and that their
output is distinguishable in a single log tail. Renamed to say so.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-27 09:36:40 +02:00
Ilker ManapandClaude Opus 5 a35e8796d2 Carry a download's progress to where somebody is looking at it
CI / test (push) Successful in 1m28s
The agent has always logged a percentage as it fetches weights, with a comment
saying a replica pulling a hundred gigabytes and one that is wedged look
identical from the control plane. They still did: the log is on the node, and
the node is not where anyone is looking when a replica has been starting for
ten minutes.

Progress now rides on the shard status and appears under the replica in `ctl
replicas` — a line rather than a column, because most replicas are not
downloading anything and a column would be empty for all of them.

It is deliberately not a state transition. Treating each chunk as one would
re-mark the shard as starting on every report and reset the timer that decides
when a slow start has become a failed one, so an hour-long download would keep
a doomed replica alive indefinitely. It arrives on its own method for that
reason, and a real transition clears it — otherwise a finished download sits in
the listing at ninety-nine percent under a shard that has been serving for an
hour.

Watchers are keyed by source rather than by shard, because a fetch is
single-flight: eight shards starting together produce one download and all
eight are waiting on it.

No percentage is invented when the server sent no length. One that stops moving
is worse than a byte count that keeps rising, so the field is absent and the
listing says "so far".

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-27 07:49:08 +02:00
Ilker ManapandClaude Opus 5 4ba84fa90e Let an agent find the leader instead of being told one address
CI / test (push) Successful in 1m32s
The second half of leadership. A standby that refuses to place but still holds
an agent's stream is worse than useless: commands travel down the stream the
agent opened, so the leader's placements fail with "no agent connected" for a
node that is plainly connected.

So a standby refuses the stream, before reading the opening message, and says
why. And an agent takes a list rather than an address, trying each in turn — a
standby refusing, a stopped control plane refusing the connection and a crashed
one never answering are the same thing from a node, and the answer to all three
is somewhere else.

`server` and `servers` are both accepted, with `server` first when both are
given: every agent configuration written before there could be a second control
plane names one address, and an operator adding a standby expects the one
already working to stay preferred. With a single address the behaviour is
exactly what it was, including the backoff — which is skipped only while there
is another address that has not just been tried, because the delay exists to
stop hammering one control plane and the next one has not been hammered.

Removed a check that asked whether one field was empty, which is how the first
run of these tests failed: the list was populated and `server` was not, and an
agent configured entirely correctly was refused by its own validation.

The tests run a real agent against a real service over h2c. The first attempt
used a plain HTTP server, and the refusal arrived as an HTTP/2 framing error
that said nothing about why — which is exactly what an operator would have seen.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-25 19:30:06 +02:00
Ilker ManapandClaude Opus 5 45e913bd10 Refresh disk and weights while the agent runs, not once when it starts
CI / test (push) Successful in 1m46s
Found by answering "where can we see this live". `ctl weights` was offering a
file for deletion that I had deleted two days earlier, and the node's disk
figure was the one it had when its agent started. Discover() is called at
registration and nowhere else, so both were frozen.

Disk is a fact about a moment, not about a machine. Sampled once, the figure
is wrong on exactly the node worth watching — the one busy filling up — and it
stays wrong until that agent restarts. The heartbeat already refreshes GPU
memory for the same reason, with a comment about noticing a foreign process
"after registration"; disk belonged beside it and I did not put it there.

The stale list cut both ways. A model fetched after registration was invisible
until a restart, so placement could not prefer the node that had just spent ten
minutes downloading it, and the disk check could not see the space it used.

Storage goes in every heartbeat, being a few numbers per filesystem. The file
list goes only when a fingerprint of paths and sizes changes, with a flag
saying the list is meant — without that, an empty list would be ambiguous
between "this node now holds nothing" and "nothing to report", and the second
reading would empty a node's inventory five seconds after it registered.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-20 09:57:25 +02:00
Ilker ManapandClaude Opus 5 774e134ed1 Refuse a node with no room, and take back only what llmgw put there
CI / test (push) Successful in 1m39s
Two halves of the same problem: nothing stopped a model being placed on a node
that could not hold it, and nothing ever removed the weights of a model that
had been deleted from the catalog.

Placement now has a disk check, shaped exactly like the memory one it sits
beside, with one addition: it is skipped on a node that already holds the
weights. A node holding the file needs no room for it, and without that the
node best placed to run a model — because it already has it — is the one most
likely to be rejected, since holding the file is what used the space.

Reclaiming is the dangerous half, so the whole design is about what it will
not do. llmgw deletes only files it fetched itself, and that is a calculation
rather than a heuristic: the cache name is a hash of the source, so the set of
wanted files can be computed from the catalog exactly. Anything without that
name was put there by an operator — scp, a shared mount, a copy by hand — and
is none of this system's business however unreferenced it looks. A model that
took a week to copy must not be removable by a command someone ran to tidy up.

The node checks every path again before unlinking it, and that duplication is
the point. The control plane knows the catalog; the node knows its disk. A
control plane that is wrong, newer than the agent, or tampered with must not be
able to talk a node into deleting something, so the agent refuses anything
outside its own cache directory or without the cache name — including a path
that tries to traverse out of it.

Listing is the default and deleting takes --collect. The summary says "asked to
remove", because each node decides, and one that refuses a path it cannot prove
it fetched is this working rather than failing.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-18 09:51:05 +02:00
Ilker ManapandClaude Opus 5 753f4e3265 Let a node say how much room it has left
CI / test (push) Failing after 1m31s
Disk was the one resource nothing reported. `statfs` was already being called
on every model directory, but only to ask whether the filesystem was a network
one — the free space it returns in the same struct was thrown away. So the
only way to find out why a node was filling up was to ssh to it, which is what
this system exists to avoid.

Reported per filesystem rather than per configured directory. Free space
belongs to the disk, not the path: two model directories on one disk are one
pool of bytes, and counting them separately would let the control plane add
24 GB to 24 GB and place a 40 GB model on a node that has 24.

Shared filesystems are summed separately from local ones and left out of a
node's own total. Space on a filer belongs to everyone mounting it, so twenty
nodes would otherwise each report the same free terabyte, and a scheduler
would place twenty models into room for one.

Nothing reported means nothing is known, everywhere: an agent too old to send
storage and a node with no model directories both send nothing, and both must
read as unknown rather than as a full disk. `ctl nodes` and the dashboard show
a dash, the metric is absent rather than zero, and a missing directory — which
is what an unmounted filer looks like — is skipped rather than reported as
having no space.

Shown as free out of total, because the first is useless without the second:
8 GB free is comfortable on a 10 TB filer and nearly full on a 10 GB root
partition, and only the second stops a model being placed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-18 09:38:57 +02:00
Ilker ManapandClaude Opus 5 b619546516 Stop trusting hardware facts that were never checked
CI / test (push) Successful in 1m32s
Three places where the system took the infrastructure's word for something
and would have failed silently on real hardware.

A declared fabric adapter that is not on the node. Fabric membership has to
be configuration — OpenSM's default subnet prefix is identical on every
fabric, so a matching prefix proves nothing — but taking it entirely on
trust was a different mistake. A typo, or a card that enumerated
differently after a reboot, produced NCCL_IB_HCA naming an adapter that
does not exist.

An adapter with no ACTIVE port. Physically linked with no subnet manager
sits in INIT: it looks healthy to anything counting adapters, carries no
data, survives a reboot, and looks like a software problem. Discovery had
recorded port state all along and placement only ever asked whether a
fabric had any adapters listed.

Both end the same way — the replica starts, passes its health checks, and
hangs on its first all-reduce, which is the failure the fabric invariant
exists to prevent arriving through a door nobody was watching. The agent
now compares declared against discovered, where both are visible for the
only time, and does not advertise a fabric that cannot carry traffic. The
reason is logged on the machine that knows it, because the operator who
typed the adapter name is the only person who can fix it. The fabric's rate
is the slowest active link, since a collective runs at the speed of its
slowest.

And NVLink topology, which no published binary could see. NVML is its only
source, the bindings need cgo, and CGO_ENABLED=0 is deliberate so the
portable binary runs on an older libc. The cost was silent: tensor groups
fall back to the lowest free indices, which is right on an SXM board with
NVSwitch and wrong on a PCIe box where bridges pair specific cards — a
group straddling two of them runs several times slower and nothing says so.
Releases now also publish an nvml build for those nodes, and
llmgw_gpu_nvlink_peers makes the difference visible: a flat zero across a
fleet means the topology is unknown rather than absent.

A test that declared mlx5_0 and mlx5_1 on a node whose sysfs held neither
had been passing, because nothing compared the two.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-17 17:29:15 +02:00
Ilker ManapandClaude Opus 5 42fd0aa31e Export what the cluster is made of, not only what it is serving
CI / test (push) Successful in 1m28s
The router published twenty-two metric families about requests, endpoints,
admission and scoring — everything about traffic and nothing about the
machines carrying it. There was no way to graph GPU usage, watch a node go
unhealthy, see a fabric fill up, or answer "was the cluster full at the
time", which is the first question anyone asks after an incident. The
agents exported nothing at all.

Exported by the control plane rather than by each agent. It already holds
every number: hardware arrives at registration and state on each heartbeat,
so this is a map read away. One scrape target for a fleet of hundreds, no
Prometheus configuration per node, no firewall rule per machine, and
nothing new running on the nodes. On the same /metrics as the traffic
figures, because correlating "the cluster was full" with "requests were
queueing" should not need two systems.

A collector rather than gauges kept current by a ticker: the numbers are
derived from state that already exists, so computing them when asked is
simpler than maintaining a copy that can drift, and nothing runs between
scrapes.

GPU utilisation is new, and is the number people actually watch. Memory
used says a model is loaded; this says whether it is doing anything, and a
fleet at ninety percent occupancy and two percent utilisation is a fleet
holding models nobody is asking for.

Adding it caught two things. utilization.gpu goes last in the nvidia-smi
query and is optional, because a driver too old to know it returns a
shorter row — requiring it made an llmgw upgrade silently stop discovering
GPUs on an older node, which is far worse than not knowing how busy a card
is. And I gave the new protobuf field number 14, which ecc_errors already
had; buf lint is why that was a moment rather than a corrupted wire format.

Absent is kept distinct from zero throughout, for the same reason as
everywhere else here: an unreported utilisation shown as a flat zero reads
as an idle fleet rather than a missing measurement, and a replica nothing
has reported would be the most idle thing in the cluster.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-17 15:09:27 +02:00
Ilker ManapandClaude Opus 5 943c23a412 Fetch a model's weights when the simple arrangement needs it
CI / test (push) Successful in 1m26s
The default arrangement is the simple one: every node keeps its own copy.
So a source naming a remote file is now fetched before the engine is
launched, rather than left to fail as a missing path minutes into a load.

Eight shards of a tensor-parallel replica start at the same instant and
want the same file; they produce one download. An interrupted fetch resumes
instead of starting over, which matters at forty gigabytes, and the
download is written beside its target and renamed only when complete — a
partial file under the model's name would be found by the next scan,
reported as present, and handed to an engine that fails on it.

The exotic arrangements need no code, which is the point. Weights on a
Lustre mount or an image exported over the fabric are simply present, and
present means nothing is fetched. The escape hatch from a distribution
mechanism is a distribution mechanism that checks first.

Wiring it up caught a regression in my own design. A bare model id —
"Qwen/Qwen2.5-7B-Instruct" — is a documented source that vLLM and SGLang
resolve themselves, and treating every non-remote source as a local path
made every existing vLLM profile fail. Only an absolute or explicitly
relative path is now checked as a file; anything else is passed through
untouched. Three agent tests failed on the same change for a better reason:
they used "/models/x", and the new check is exactly the one that catches
that.

Whole repositories of shards are deliberately not fetched here. vLLM and
SGLang do that well already, and a second snapshot downloader would be work
spent arriving back where we started.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-17 08:46:03 +02:00
Ilker ManapandClaude Opus 5 c13c567cc5 Know where the weights are, without owning the storage
CI / test (push) Successful in 1m32s
Storage will be different at every installation — Lustre, NFS over RDMA, an
image exported with SRP or NVMe-oF, local NVMe, an rsync — so llmgw observes
it rather than managing it. An agent told which directories to look in
reports what it can see; how the files got there is nobody's business here,
and a node told nothing reports nothing and behaves exactly as every node
did before this existed.

That fact buys two things. Placement prefers a node that already holds the
model over one that must first move tens of gigabytes, as a preference and
never a filter: fetching them is a valid answer, and refusing to place would
turn a slow start into no start at all. And ctl status shows what each
fabric holds.

Per fabric because fabrics are not connected to one another. Weights in
ib-a are not weights in ib-b — the only path between them is the management
network — so a model seeded into one fabric leaves the rest of the cluster
unable to serve it without a slow copy, and nothing said so before now. One
shared filer counts the same as twenty local copies, because "can this
fabric serve it" is the question being asked.

Three distinctions the tests hold to, because each is a way to get this
quietly wrong. A node that was never asked to look must rank with one that
looked and has nothing, or enabling the feature on a single node would
drain every other. An empty directory is not weights, because a
half-finished download looks exactly like one and would send placement to a
node whose engine then fails to load. And local storage is never mistaken
for shared: a filer read as local costs an unnecessary copy, while local
read as shared would have the cluster believe a model is everywhere when it
is on one node.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-17 08:21:16 +02:00
Ilker ManapandClaude Opus 5 1431426db0 Finish adopting an engine instead of stopping at "it is alive"
CI / test (push) Successful in 1m26s
Adoption set a shard to Starting and started a liveness poll, and that was
all. Nothing health-checked it, so nothing ever moved it to Ready. The
control plane then waited out the profile's startup timeout and killed a
perfectly healthy engine so it could start an identical one.

An agent restart exists precisely so that engines are not interrupted. It
was costing every model on the node a full reload, minutes of it, which is
the failure adoption was written to prevent.

Measured on node05 while deploying today's other changes: the engine
answered /health the whole time and the replica sat in Starting for three
minutes until the timeout reaped it. I had seen this earlier in the session
and worked around it by killing the engine to force a clean restart, which
made the symptom go away and left the cause in place.

An adopted shard now takes the same two paths a freshly started one does: a
rank that serves HTTP is health-checked, a worker is judged by staying
alive. Run in the background, because recovery happens before the agent
connects and a slow check must not delay registration. An engine that will
not answer is left for the control plane to replace rather than killed
locally, which would race the decision it already has a timeout for.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 23:58:53 +02:00
Ilker ManapandClaude Opus 5 d71d785598 Report node memory even when GPU discovery fails
CI / test (push) Successful in 1m31s
Deploying the memory-aware placement showed node01 to node04 reporting 7G
and node05 reporting nothing, on a machine whose /proc/meminfo plainly says
32 GB. node05 has no nvidia-smi, so GPU discovery returns an error, Discover
returns with it, and the memory read — which has nothing to do with cards —
never happened.

That is the node whose memory matters most, because a CPU profile is what a
GPU-less node will be asked to run, and min_memory_gb would have excluded it
from everything.

Read first now, before any path that can return early. The test fails
against the old order.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 23:50:53 +02:00
Ilker ManapandClaude Opus 5 3081c6f69b Place on nodes that can actually hold the model
CI / test (push) Successful in 1m23s
Placement had no idea how much memory a node has or a model needs. A CPU
profile has no card to be free, so eligibleNodes accepted every ready node:
Qwen2.5-Coder 14B, whose working set is about 24 GB, would have been placed
just as happily on one of the 8 GB nodes, which reports itself perfectly
healthy right up until the OOM killer arrives.

node_selector was yesterday's stopgap and it is the operator restating by
hand something the system can know. Agents now report MemTotal, profiles
declare min_memory_gb, and placement filters on it, naming what was short —
"has 8 GB of memory, needs 24" is actionable where "no candidates were
considered" is not. The label selector stays, because "this node is for
coding models" is a real thing to want to say that memory does not express.

Two deliberate non-exclusions. A profile with no requirement fits anywhere,
which is every profile that exists today. And a node that reports no memory
is still usable: an agent older than the field says nothing, and letting a
control plane upgrade quietly empty half a fleet is a worse failure than the
one this prevents.

ctl nodes grows a MEM column showing "-" rather than 0 for a node that did
not say, because an old agent is not a small machine.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 23:12:44 +02:00
Ilker ManapandClaude Opus 5 ea87021b5c Correct what the previous commit claimed about --jinja
CI / test (push) Successful in 1m30s
9fc098f said passing --jinja fixes tool calling. It does not. llama.cpp
build 10991 has jinja enabled by default — "--jinja, --no-jinja ... (default:
enabled)" — so the flag changed nothing, and tool calls came back as text
before and after it in exactly the same way.

The flag is worth keeping for a different reason, and the comment now says
that one: it pins how prompts are built, so an engine upgrade cannot change
it underneath a running fleet. Older builds do default to the generic
template.

What actually happens is that llama.cpp renders the tools correctly — the
prompt from /apply-template carries the <tools> block and the instruction to
reply in <tool_call> tags — and qwen2.5-coder answers with a markdown JSON
block instead. 3B and 7B both, and tool_choice "required" does not constrain
it either. That is the model, not the plumbing, and no flag here will fix
it.

Recording it because a wrong explanation in a commit message is worse than
no explanation: the next person to see tool calls arriving as text would
have checked --jinja, found it already set, and had nowhere to go.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 21:30:22 +02:00
Ilker ManapandClaude Opus 5 9fc098fd5b Start llama.cpp with the model's own chat template
CI / test (push) Successful in 1m25s
Tool calling did not work, and it looked like the model's fault. Asked to
use a tool, qwen2.5-coder produced exactly the right call —
{"name": "list_files", "arguments": {"path": "."}} — as plain reply text,
with tool_calls null and finish_reason "stop". Every OpenAI-compatible
client, opencode among them, sees a model that ignores the tools it was
given.

The cause is that llama-server falls back to a generic chat template unless
--jinja is passed, and the generic one neither formats the tool definitions
the way the model was trained to read them nor parses what comes back into
tool_calls. It affects ordinary chat too, for the same reason.

A profile can still pass --no-jinja, because a model whose bundled template
is broken has to be serviceable without editing the adapter.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 21:20:55 +02:00
Ilker ManapandClaude Opus 5 5b425c32e5 Ship binaries with releases, and ask engines whether our flags still exist
CI / test (push) Successful in 1m31s
A release was a git tag. Installing llmgw on a node meant having a Go
toolchain, and the onboarding script copied a binary from wherever it was run —
which works and quietly makes whoever runs it the build server, with the fleet
ending up on whatever was in their working tree. Tags now build static
linux/amd64, linux/arm64 and darwin binaries and attach them. CGO_ENABLED=0 is
the point: it has to run on a node whose libc is older than the builder's, and
llmgw has no C dependency because modernc.org/sqlite is pure Go precisely so
this stays true. Verified: "not a dynamic executable", runs on a node, reports
its version.

`ctl engine-check` closes the other half of the phase 4 gap. llmgw's launch
arguments are read from each engine's documentation, and engines rename flags
between versions; when that happens the failure arrives minutes into a model
load, in the engine's own error message, on a node nobody was watching. It
builds the widest command llmgw would ever produce — multi-node, since a flag
that only appears there is the one nobody notices has gone — and checks each
flag against the engine's own --help. No GPU: a CLI prints its help anywhere.
Verified against llama.cpp b10991, all seven flags accepted.

Flags are matched on a word boundary, so --port is not satisfied by
--port-range. Without that, a renamed flag would sail through the check that
exists to catch renamed flags.

It also warns when the help text looks truncated, which is how the first run
went: llama.cpp's help cut to 400 of its 725 lines reported five flags as
missing that the running cluster uses.

TestSidecarRunsBeforeEngine was flaky under a full run, and worse than flaky —
its wait loop fell through on timeout, so a slow machine turned the ordering
assertion into a no-op and the failure surfaced later as something else. It now
asserts, with a deadline that suits a machine running every other package at
the same time.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 16:44:29 +02:00
Ilker ManapandClaude Opus 5 c1ac2f022f Onboard a node with a script, and find two examples that never worked
New nodes had been joined by hand, four times, by me. There was no procedure,
so there was nothing to be wrong — and nothing to be right either. Two scripts
now: provision-node.sh makes the VM on Proxmox, onboard-node.sh gives it an
identity. They are separate because they are run by different people with
different access, and the second must run where the certificate authority is,
which is the one part that cannot be delegated.

Running them turned up why phase 4 was never verified. FabricAttachment
carried no koanf tags, so the `name:` key the shipped example documents bound
to nothing and `rate_gbps` was never read at all. An agent configured exactly
as instructed refused to start with "fabrics[0]: name is required" — naming
the key the operator had just written. Every fabric in this project had been
configured in a Go test, where the tags do not matter.

The server example did not load either: its models had no source, so it failed
validation the moment anything tried to parse it.

Both examples are now parsed by a test. A published example that has never
been loaded is a guess, and these two had been guesses since they were
written.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 12:28:36 +02:00
Ilker ManapandClaude Opus 5 058ee382fa An agent reporting nothing is reporting something
CI / test (push) Successful in 1m18s
The previous commit taught the reconciler to let go of shards an agent says
it is not running. It made no difference on the cluster, because the service
returned early when the agent's list was empty — which is precisely the case
that carries the news.

So the fix was dead code in production while its unit tests passed, and they
passed because they called the reconciler directly. The test added here goes
through the real stream instead, and asserts only that an agent running
nothing reaches the reconciler at all.

That is the lesson worth keeping: a test that calls the function under test
directly cannot tell you the caller never calls it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 10:36:35 +02:00
Ilker ManapandClaude Opus 5 aef1c143c5 Let go of shards an agent says it is not running
CI / test (push) Successful in 1m19s
Adoption handled "the agent has something we do not know about". The mirror
image was missing: "we think the agent has something it does not".

Both follow from the same rule — the fleet is authoritative about what is
running (plan §6.5) — and without the second half an engine that dies while
its agent survives leaves the control plane believing a replica is Ready
forever. Measured on the cluster: the engine was killed, the agent restarted
and registered with nothing running, and the replica stayed Ready pointing at
a dead port for two and a half minutes until I stopped watching. Traffic
survived, because the breaker took the endpoint out and retries covered it —
24 requests, none failed — so the only symptom was a cluster quietly running a
third short.

A registration follows a fresh connection, so anything dispatched over a
previous one is not running by definition; there is no window where a shard is
legitimately started but unreported.

The previous commit's disown rule was too broad, which this turned up: when a
known replica had a live shard it disowned everything the agent reported for
it, including the shards we already knew. A reconnecting agent would have been
told to stop the replica that was serving. It now disowns only what it does
not recognise.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 10:30:49 +02:00
Ilker ManapandClaude Opus 5 501db3d3e8 Add the llama.cpp engine, and let a profile ask for no GPU
llama.cpp is what makes a cluster with no cards useful: it serves the same
OpenAI API on CPU, so the whole path — placement, supervision, scraping,
scheduling, admission — can be exercised end to end on ordinary machines.

Three things had to give way for it.

A profile may now omit its GPU class, and that is how it says it runs on the
CPU. Only engines that can actually serve without a card may omit it; for
vLLM an omitted class stays an error, because otherwise a typo becomes a
replica placed on a machine with no hardware and diagnosed minutes later
during model loading. Placement spreads CPU replicas instead of bin packing
them, since unlike GPUs there is no allocation to stop two of them sharing a
machine's cores.

Metric mappings are now per engine rather than per cluster. llama.cpp calls
the same three numbers requests_processing, requests_deferred and
kv_cache_usage_ratio, and a single global mapping would leave half a mixed
fleet unmeasurable. An empty mapping still defaults to vLLM's names; one that
names its own Running metric is taken as a complete statement, so the fields
it leaves blank stay blank rather than being filled with names that engine
cannot have.

The adapter refuses multi-node and tensor-parallel profiles. llama.cpp splits
across local GPUs by a different mechanism than this adapter drives, and
accepting either would produce a replica that starts and then serves from one
machine while the catalog believes it has several.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 08:14:05 +02:00
Ilker ManapandClaude Opus 5 ec1b6b04df Fix an agent that could neither explain itself nor stop
CI / test (push) Successful in 54s
Two bugs found while verifying mTLS against real machines.

session cancelled its own derived context and then asked that context
whether the agent was shutting down. The answer was always yes, so every
stream error read as a clean close: the log said err=<nil>, the backoff
reset, and an agent whose certificate the control plane refused hammered it
forever at the base interval with nothing to diagnose. It now keeps the
parent context to answer that question, and a refusal reaches the operator
naming both the certificate and the claim.

Cancelling the context also did not stop the agent. HTTP/2 watches the
context while the request body is being written, and a bidirectional stream
spends its life blocked on the read side instead, so the read never returned.
Measured on a deployed node: `systemctl stop llmgw-agent` took 90 seconds and
ended in SIGKILL, on every restart. Closing the response when the context
ends is what actually unblocks it.

TestAgentStopsWhenContextEnds hangs reliably without the second fix, which is
the only reason to trust that it tests it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 08:03:21 +02:00
Ilker ManapandClaude Opus 5 1e3cafdc86 Add a private CA and mutual TLS for the agent stream
A node's identity was whatever the agent said it was. With mutual TLS the
control plane compares the client certificate's common name against the
claimed node id and refuses the connection when they disagree, so identity
becomes something a node proves rather than something it picks.

A public authority cannot supply these certificates: Let's Encrypt and its
peers stopped issuing the clientAuth usage, and Go verifies client chains
against it. Hence internal/tlsconf/ca.go, a small authority whose key lives
on one machine and whose root is trusted everywhere, and `llmgw ctl cert`
over it so issuing is reproducible instead of remembered openssl.

The server certificate's hosts matter more than they look: hostname
verification reads subject alternative names and ignores the common name
entirely, so a certificate without the address agents dial — bare IP
included — is rejected no matter what its subject says. There is a test for
exactly that, because it is the failure everyone hits once.

requireIdentity stays wired to false until the configuration lands, so this
commit changes no running behaviour.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 07:28:56 +02:00
ilkerandClaude Opus 5 e8d90cf375 Treat a zombie as dead, and test fairness where it is deterministic
CI / test (push) Successful in 52s
CI went red on Linux with two failures that never appear on macOS. Both were
worth the trip.

The first is a real bug. processAlive used kill(pid, 0), which succeeds on a
zombie — a process that has exited and is only waiting to be reaped. That
happens for real whenever an engine's parent dies before it does and nothing
reaps the orphan, which in a container is the normal case: PID 1 is usually the
workload rather than an init. The supervisor would then report a dead adopted
engine as running forever, and hold its GPUs against every future placement.
Zombies are now detected through procfs on Linux, where the answer exists, and
the check degrades to its old behaviour elsewhere rather than to something worse.

The second was a bad test. TestTenantFairnessWithinBand asserted on the order
goroutines sent to a channel after being admitted, which is the order the Go
scheduler woke them, not the order the dispatcher chose. Under load it measured
the runtime. The rotation itself lives in bandQueue.pop, which is pure, so it is
tested there — including what happens when a tenant runs out mid-rotation and
when a cancelled waiter is removed. The controller-level test now asserts the
thing that is actually stable: nobody is starved.

Verified with three consecutive `go test -race ./...` runs in a Linux container.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 06:34:08 +02:00
ilkerandClaude Opus 5 1d1a6aebb0 Phase 4: make a multi-node replica able to start
CI / test (push) Failing after 53s
Placement and environment generation had landed early, which made multi-node
look further along than it was. A replica spanning nodes could not come up at
all, and all three reasons came down to assumptions that only hold on one node.

Not every rank serves HTTP. The agent health-checked every shard at its own
port, but only the leader answers; workers timed out, reported Failed and took
the replica with them. Engine.ServesHTTP now says which ranks serve, and a
worker is judged by staying alive. That is deliberately weaker evidence: the
replica's real readiness is the leader answering, which only happens once every
worker has joined.

A shard is not always one process. Engine.Commands returns a sequence — every
command but the last is a sidecar kept alive for the shard's lifetime and torn
down with it, and the last one's exit is the shard's. vLLM under Ray is why: the
leader runs a Ray head and then the server against it, while a worker runs only
the join and no vLLM process at all. RayCommand had been written and tested but
never called, so launch_mode: ray would have run vllm serve against a cluster
that did not exist. Sidecars are killed with the shard, because a Ray head left
behind holds the port the next replica needs.

Start order was backwards. Workers went first, on the theory that the head
should wait for them. Both engines put the rendezvous point on rank 0, so a
worker started first has nothing to connect to. vLLM's server blocks until the
Ray cluster has the GPUs it needs, so the leader can start immediately and waits
on its own. A command can now also require that rendezvous point to be listening
before the next starts, bounded by a timeout so a head that never appears fails
the shard instead of hanging it.

Stop was also killing only the engine, leaving sidecars behind.

None of this is verified against real engines — it is tested with stub
processes. The Ray sequencing, and which launch mode a given vLLM version wants,
can only be confirmed on hardware.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 06:20:03 +02:00
ilkerandClaude Opus 5 75a8e76706 Survive a control plane restart without orphaning live engines
CI / test (push) Successful in 1m44s
Not persisting replica state left one hole: restarting the control plane made it
forget every replica while the engines kept running. They held GPUs the
inventory believed were free, so the next placement failed to allocate, with an
error naming the new process rather than the old one.

The fix belongs on the agent, not in a database. A row can say "running" about a
process that died; the fleet cannot.

- the supervisor writes the full shard spec, not just a pid and command line. A
  pid identifies a process; the spec is what lets it be described back to the
  control plane and matched to a replica.
- Adopt takes over an engine a previous agent left running. It is not this
  process's child, so it cannot be waited on: it is watched by polling and
  stopped by signalling its group directly. Its earlier output is gone and the
  log says so rather than presenting emptiness as silence.
- every Register reports what the agent is running, not only the first, because
  a reconnect may be a control plane restart and has to recover the same way.
- the reconciler rebuilds replicas from those reports and reclaims their GPUs.
  Anything whose model or profile left the catalog is stopped; nothing will
  route to it and it is holding cards.
- an engine the agent cannot identify is killed. A process holding GPUs that
  nothing can describe is worse than no process, because placement hands those
  GPUs out again.

Stop was also wrong for adopted shards: it checked for an exec.Cmd, which they
do not have, and reported them stopped without killing anything.

TestAgentReconnects had been passing for no reason. httptest's
CloseClientConnections does nothing to an h2c stream — prior-knowledge h2c
hijacks the connection and httptest stops tracking hijacked ones — so the agent
never reconnected, and the assertion on the connection map passed on a stale
entry. Tests now sever connections through their own listener and count opened
streams.

Plan §11 also records what multi-node still needs, since placement landing early
makes it look further along than it is: workers never become Ready because the
agent health-checks every shard while only rank 0 serves HTTP; RayCommand is
written and tested but never called; and startup is fire-and-forget.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 06:15:04 +02:00
ilkerandClaude Opus 5 2373726efd Agent stream: connect the fleet to the control plane
CI / test (push) Failing after 1m29s
One bidirectional connect-go stream per node, carrying registration, heartbeats
and shard status up, and start, stop and drain down. The agent dials out: GPU
nodes sit behind firewalls far more often than a control plane does, and an
outbound connection needs no inbound rule on every node in the fleet.

- registration carries the whole hardware inventory, so there is no separate
  discovery call and a reconnecting agent refreshes what the scheduler knows.
  The fabric labels travel with it; they cannot be inferred from the wire, so
  losing them in transit would silently disable multi-node placement.
- agentsvc is both the stream handler and the reconciler's dispatcher, because
  it holds the open streams and is therefore the only thing that can deliver a
  command to a node.
- the agent validates a profile before launching anything, since an engine that
  refuses a profile does so after minutes of loading, then supervises the
  process and reports every transition with the engine's output tail on failure.
- reconnects forever with jittered backoff. A control plane restart must not
  require touching every GPU node, and a fleet must not reconnect in lockstep
  and knock it over again. Engines keep serving throughout, because the router
  talks to them directly.

llmgw agent is real now, and llmgw server runs a control plane whenever any
model declares a profile. The static endpoint list stays for router-only runs.

Verified with real binaries as separate processes: the agent registers, a
replica is placed, an engine launches through the vLLM adapter's actual argument
construction, streaming traffic is served, and killing the agent moves the node
through unreachable to lost with placement explaining why nothing can run.

config.Model and catalog.Model were the same thing described twice, so the
router now reads catalog entries directly and the validation rules live in one
place.

Still missing: mTLS. The stream is plaintext HTTP/2 and must stay on a trusted
network until that lands.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 02:48:21 +02:00
ilkerandClaude Opus 5 55417546fc Phase 2 (2/2): NVML backend behind a build tag
CI / test (push) Successful in 1m37s
NVML is the only source of NVLink topology, and that topology is what keeps a
tensor-parallel group off the slow path inside a node. It needs cgo, so it sits
behind the nvml tag and the default build keeps using nvidia-smi.

Discover() picks the backend and falls back to nvidia-smi when NVML fails,
logging the fallback rather than performing it silently: on a node that is meant
to have working NVML, a quiet downgrade hides a broken driver installation and
costs the scheduler its topology.

CI now compiles the tagged build. That immediately paid for itself: ErrNoNVML
was declared only in the untagged file, so the tests did not compile under
-tags nvml. It is now declared where both builds can see it.

Not verified: the NVML path has never run against a driver, because there is no
GPU machine available. The NVLink domains it reports should be treated as
unverified until someone runs `llmgw agent inventory` on a real node.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 02:05:25 +02:00
ilkerandClaude Opus 5 6a13e3dddf Phase 2 (1/2): node discovery, engine adapters, process supervisor
CI / test (push) Successful in 45s
Everything here works without GPUs and is covered by tests. The control plane
connection is not built yet, so llmgw agent itself is still a stub and the phase
exit criterion is not met.

- discovery: IB from /sys/class/infiniband, parsing the formats sysfs actually
  uses and telling native InfiniBand from RoCE; GPUs via nvidia-smi, the
  cgo-free path, with health flags for uncorrected ECC and memory already held
  by another process. A node without IB is not an error, it is a single-node
  island.
- engines: vLLM and SGLang command and environment construction, kept free of
  process handling so it stays testable. The NCCL environment is the part the
  plan marks critical: NCCL_IB_HCA lists only the chosen fabric's adapters,
  because leaving it open lets NCCL pick an adapter on a fabric where the peer
  is unreachable, and the job then hangs instead of failing.
- validation before launch: no mixed GPU types in a tensor-parallel group, the
  node/GPU/TP arithmetic has to add up, and fp8 is refused below compute
  capability 8.9 rather than silently falling back to a slower path.
- supervisor: process groups, because engines fork workers that hold GPU memory
  and outlive a signal sent only to the leader; a bounded log tail, since engine
  output is the only diagnosis when loading fails; Starting separate from
  Loading, because a 70B model legitimately takes minutes; and orphan adoption
  through pid files fingerprinted with the command line, since pids get reused
  and adopting an unrelated process is worse than leaking the original.
- readiness is two questions: /health says the process is up, /v1/models says
  the weights loaded. Routing on /health alone sends traffic into a loading model.
- llmgw agent inventory reports what the scheduler would see on a node.

One plan correction: GPU class sizes come from the driver in GiB, which does not
always match the marketing name. An L40S is sold as 48GB and reports 44.99 GiB,
so its class is l40s-45g, not l40s-48g. Consistency matters more than matching
the box, because that number decides whether a model fits. Plan §2 and §5.1
updated.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 02:01:59 +02:00