Files
LocalAI/docs
Richard Palethorpe 8e43842175 feat(vllm, distributed): tensor parallel distributed workers (#9612)
* feat(vllm): build vllm from source for Intel XPU

Upstream publishes no XPU wheels for vllm. The Intel profile was
silently picking up a non-XPU wheel that imported but errored at
engine init, and several runtime deps (pillow, charset-normalizer,
chardet) were missing on Intel -- backend.py crashed at import time
before the gRPC server came up.

Switch the Intel profile to upstream's documented from-source
procedure (docs/getting_started/installation/gpu.xpu.inc.md in
vllm-project/vllm):

  - Bump portable Python to 3.12 -- vllm-xpu-kernels ships only a
    cp312 wheel.
  - Source /opt/intel/oneapi/setvars.sh so vllm's CMake build sees
    the dpcpp/sycl compiler from the oneapi-basekit base image.
  - Hide requirements-intel-after.txt during installRequirements
    (it used to 'pip install vllm'); install vllm's deps from a
    fresh git clone of vllm via 'uv pip install -r
    requirements/xpu.txt', swap stock triton for
    triton-xpu==3.7.0, then 'VLLM_TARGET_DEVICE=xpu uv pip install
    --no-deps .'.
  - requirements-intel.txt trimmed to LocalAI's direct deps
    (accelerate / transformers / bitsandbytes); torch-xpu, vllm,
    vllm_xpu_kernels and the rest come from upstream's xpu.txt
    during the source build.
  - requirements.txt: add pillow + charset-normalizer + chardet --
    used by backend.py and missing on the Intel install profile.
  - run.sh: 'set -x' so backend startup is visible in container
    logs (the gRPC startup error path was previously opaque).

Also adds a one-line docs example for engine_args.attention_backend
under the vLLM section, since older XE-HPG GPUs (e.g. Arc A770)
need TRITON_ATTN to bypass the cutlass path in vllm_xpu_kernels.

Tested end-to-end on an Intel Arc A770 with Qwen2.5-0.5B-Instruct
via LocalAI's /v1/chat/completions.

Assisted-by: Claude:claude-opus-4-7 [Claude Code]
Signed-off-by: Richard Palethorpe <io@richiejp.com>

* feat(vllm): add multi-node data-parallel follower worker

vLLM v1's multi-node story is one process per node sharing a DP
coordinator over ZMQ -- the head runs the API server with
data_parallel_size > 1 and followers run `vllm serve --headless ...`
with matching topology. Today LocalAI can already configure DP on the
head via the engine_args YAML map, but there's no way to bring up the
follower nodes -- so the head sits waiting for ranks that never
handshake.

Add `local-ai p2p-worker vllm`, mirroring MLXDistributed's structural
precedent (operator-launched, static config, no NATS placement). The
worker:

  - Optionally self-registers with the frontend as an agent-type node
    tagged `node.role=vllm-follower` so it's visible in the admin UI
    and operators can scope ordinary models away via inverse
    selectors.
  - Resolves the platform-specific vllm backend via the gallery's
    "vllm" meta-entry (cuda*, intel-vllm, rocm-vllm, ...).
  - Runs vLLM as a child process so the heartbeat goroutine survives
    until vLLM exits; forwards SIGINT/SIGTERM so vLLM can clean up its
    ZMQ sockets before we tear down.
  - Validates --headless + --start-rank 0 is rejected (rank 0 is the
    head and must serve the API).

Backend run.sh dispatches `serve` as the first arg to vllm's own CLI
instead of LocalAI's backend.py gRPC server -- the follower speaks
ZMQ directly to the head, there is no LocalAI gRPC on the follower
side. Single-node usage is unchanged.

Generalises the gallery resolution helper into findBackendPath()
shared by MLX and vLLM workers; extracts ParseNodeLabels for the
comma-separated label parsing both use.

Ships with two compose recipes (`docker-compose.vllm-multinode.yaml`
for NVIDIA, `docker-compose.vllm-multinode.intel.yaml` for Intel
XPU/xccl) plus `tests/e2e/vllm-multinode/smoke.sh`. Both vendors are
supported (NCCL for CUDA/ROCm, xccl for XPU) but mixed-vendor DP is
not -- PyTorch's process group requires every rank to use the same
collective backend, and NCCL/xccl/gloo don't interoperate.

Out of scope (deferred): SmartRouter-driven placement of follower
ranks via NATS backend.install events, follower log streaming through
/api/backend-logs, tensor-parallel across nodes, disaggregated
prefill via KVTransferConfig.

Assisted-by: Claude:claude-opus-4-7 [Claude Code]
Signed-off-by: Richard Palethorpe <io@richiejp.com>

* test(vllm): CPU-only end-to-end test for multi-node DP

Adds tests/e2e/vllm-multinode/, a Ginkgo + testcontainers-go suite
that brings up a head + headless follower from the locally-built
local-ai:tests image, bind-mounts the cpu-vllm backend extracted by
make extract-backend-vllm so it's seen as a system backend (no gallery
fetch, no registry server), and asserts a chat completion across both
DP ranks. New `make test-e2e-vllm-multinode` target wires the docker
build, backend extract, and ginkgo run together; BuildKit caches both
images so re-runs only rebuild what changed. Tagged Label("VLLMMultinode")
so the existing distributed suite isn't pulled along.

Two pre-existing bugs surfaced by the test:

1. extract-backend-% (Makefile) failed for every backend, because all
   backend images end with `FROM scratch` and `docker create` rejects
   an image with no CMD/ENTRYPOINT. Fixed by passing
   --entrypoint=/run.sh -- the container is never started, only
   docker-cp'd, so the path doesn't have to exist; we just need
   anything that satisfies the daemon's create-time validation.

2. backend/python/vllm/run.sh's `serve` shortcut for the multi-node DP
   follower exec'd ${EDIR}/venv/bin/vllm directly, but uv bakes an
   absolute build-time shebang (`#!/vllm/venv/bin/python3`) that no
   longer resolves once the backend is relocated to BackendsPath.
   _makeVenvPortable's shebang rewriter only matches paths that
   already point at ${EDIR}, so the original shebang slips through
   unchanged. Fixed by exec-ing ${EDIR}/venv/bin/python with the script
   as an argument -- Python ignores the script's shebang in that case.

The test fixture caps memory aggressively (max_model_len=512,
VLLM_CPU_KVCACHE_SPACE=1, TORCH_COMPILE_DISABLE=1) so two CPU engines
fit on a 32 GB box. TORCH_COMPILE_DISABLE is currently mandatory for
cpu-vllm: torch._inductor's CPU-ISA probe runs even with
enforce_eager=True and needs g++ on PATH, which the LocalAI runtime
image doesn't ship -- to be addressed in a follow-up that bundles a
toolchain in the cpu-vllm backend.

Assisted-by: Claude:claude-opus-4-7 [Claude Code]
Signed-off-by: Richard Palethorpe <io@richiejp.com>

* feat(vllm): bundle a g++ toolchain in the cpu-vllm backend image

torch._inductor's CPU-ISA probe (`cpu_model_runner.py:65 "Warming up
model for the compilation"`) shells out to `g++` at vllm engine
startup, regardless of `enforce_eager=True` -- the eager flag only
disables CUDA graphs, not inductor's first-batch warmup. The LocalAI
CPU runtime image (Dockerfile, unconditional apt list) does not ship
build-essential, and the cpu-vllm backend image is `FROM scratch`,
so any non-trivial inference on cpu-vllm crashes with:

  torch._inductor.exc.InductorError:
    InvalidCxxCompiler: No working C++ compiler found in
    torch._inductor.config.cpp.cxx: (None, 'g++')

Bundling the toolchain in the CPU runtime image would bloat every
non-vllm-CPU deployment and force a single GCC version on backends
that may want clang or a different version. So this lives in the
backend, gated to BUILD_TYPE=='' (the CPU profile).

`package.sh` snapshots g++ + binutils + cc1plus + libstdc++ + libc6
(runtime + dev) + the math libs cc1plus links (libisl/libmpc/libmpfr/
libjansson) into ${BACKEND}/toolchain/, mirroring /usr/... layout. The
unversioned binaries on Debian/Ubuntu are symlink chains pointing into
multiarch packages (`g++` -> `g++-13` -> `x86_64-linux-gnu-g++-13`,
the latter in `g++-13-x86-64-linux-gnu`), so the package list resolves
both the version and the arch-triplet variant. Symlinks /lib ->
usr/lib and /lib64 -> usr/lib64 are recreated under the toolchain
root because Ubuntu's UsrMerge keeps them at /, and ld scripts
(`libc.so`, `libm.so`) hardcode `/lib/...` paths that --sysroot
re-roots into the toolchain.

The unversioned `g++`/`gcc`/`cpp` symlinks are replaced with wrapper
shell scripts that resolve their own location at runtime and pass
`--sysroot=<toolchain>` and `-B <toolchain>/usr/lib/gcc/<triplet>/<ver>/`
to the underlying versioned binary. That's how torch's bare `g++ foo.cpp
-o foo` invocation finds cc1plus (-B), system headers (--sysroot), and
the bundled libstdc++ (--sysroot, --sysroot is recursive into linker).

`run.sh` adds the toolchain bin dir to PATH and the toolchain's
shared-lib dir to LD_LIBRARY_PATH -- everything else (header search,
linker search, executable search) is encapsulated in the wrappers.
No-op for non-CPU builds, the dir doesn't exist there.

The cpu-vllm image grows by ~217 MB. Tradeoff is acceptable -- cpu-vllm
is already a niche profile (few users compared to GPU vllm) and the
alternative is a backend that crashes at first inference unless the
operator manually sets TORCH_COMPILE_DISABLE=1, which silently disables
all torch.compile optimizations.

Drops `TORCH_COMPILE_DISABLE=1` from tests/e2e/vllm-multinode -- the
smoke now exercises the real compile path through the bundled toolchain.
Test runtime is +20s for the warmup compile, still <90s end to end.

Assisted-by: Claude:claude-opus-4-7 [Claude Code]
Signed-off-by: Richard Palethorpe <io@richiejp.com>

* fix(vllm): scope jetson-ai-lab index to L4T-specific wheels via pyproject.toml

The L4T arm64 build resolves dependencies through pypi.jetson-ai-lab.io,
which hosts the L4T-specific torch / vllm / flash-attn wheels but also
transparently proxies the rest of PyPI through `/+f/<sha>/<filename>`
URLs. With `--extra-index-url` + `--index-strategy=unsafe-best-match`
uv would pick those proxy URLs for ordinary PyPI packages —
anthropic/openai/propcache/annotated-types — and fail when the proxy
503s. Master is hitting the same bug on its own l4t-vllm matrix entry.

Switch the l4t13 install path to a pyproject.toml that marks the
jetson-ai-lab index `explicit = true` and pins only torch, torchvision,
torchaudio, flash-attn, and vllm to it via [tool.uv.sources]. uv won't
consult the L4T mirror for anything else, so transitive deps fall back
to PyPI as the default index — no exposure to the proxy 503s.

`uv pip install -r requirements.txt` ignores [tool.uv.sources], so the
l4t13 branch in install.sh now invokes `uv pip install --requirement
pyproject.toml` directly, replacing the old requirements-l4t13*.txt
files. Other BUILD_PROFILEs continue using libbackend.sh's
installRequirements and never read pyproject.toml.

Local resolution test (x86_64, dry-run) confirms uv hits the L4T
index for torch and falls through to PyPI for everything else.

Assisted-by: claude-code:claude-opus-4-7-1m [Read] [Edit] [Bash] [Write]
Signed-off-by: Richard Palethorpe <io@richiejp.com>

---------

Signed-off-by: Richard Palethorpe <io@richiejp.com>
2026-05-06 00:22:50 +02:00
..
2026-03-27 21:26:55 +00:00
2025-11-19 22:25:33 +01:00

LocalAI website

LocalAI documentation website

Requirement

In this project, the Docsy theme component is pulled in as a Hugo module, together with other module dependencies:

$ hugo mod graph
hugo: collected modules in 566 ms
hugo: collected modules in 578 ms
github.com/google/docsy-example github.com/google/docsy@v0.5.1-0.20221017155306-99eacb09ffb0
github.com/google/docsy-example github.com/google/docsy/dependencies@v0.5.1-0.20221014161617-be5da07ecff1
github.com/google/docsy/dependencies@v0.5.1-0.20221014161617-be5da07ecff1 github.com/twbs/bootstrap@v4.6.2+incompatible
github.com/google/docsy/dependencies@v0.5.1-0.20221014161617-be5da07ecff1 github.com/FortAwesome/Font-Awesome@v0.0.0-20220831210243-d3a7818c253f

If you want to do SCSS edits and want to publish these, you need to install PostCSS

npm install

Running the website locally

Building and running the site locally requires a recent extended version of Hugo. You can find out more about how to install Hugo for your environment in our Getting started guide.

Once you've made your working copy of the site repo, from the repo root folder, run:

hugo server

Running a container locally

You can run docsy-example inside a Docker container, the container runs with a volume bound to the docsy-example folder. This approach doesn't require you to install any dependencies other than Docker Desktop on Windows and Mac, and Docker Compose on Linux.

  1. Build the docker image

    docker-compose build
    
  2. Run the built image

    docker-compose up
    

    NOTE: You can run both commands at once with docker-compose up --build.

  3. Verify that the service is working.

    Open your web browser and type http://localhost:1313 in your navigation bar, This opens a local instance of the docsy-example homepage. You can now make changes to the docsy example and those changes will immediately show up in your browser after you save.

Cleanup

To stop Docker Compose, on your terminal window, press Ctrl + C.

To remove the produced images run:

docker-compose rm

For more information see the Docker Compose documentation.

Troubleshooting

As you run the website locally, you may run into the following error:

➜ hugo server

INFO 2021/01/21 21:07:55 Using config file: 
Building sites … INFO 2021/01/21 21:07:55 syncing static files to /
Built in 288 ms
Error: Error building site: TOCSS: failed to transform "scss/main.scss" (text/x-scss): resource "scss/scss/main.scss_9fadf33d895a46083cdd64396b57ef68" not found in file cache

This error occurs if you have not installed the extended version of Hugo. See this section of the user guide for instructions on how to install Hugo.

Or you may encounter the following error:

➜ hugo server

Error: failed to download modules: binary with name "go" not found

This error occurs if you have not installed the go programming language on your system. See this section of the user guide for instructions on how to install go.