happyz
/
llama.cpp
mirror of https://github.com/ggerganov/llama.cpp.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

rpc : update documentation (#16441) 

Update the README file to match the newly added functionality of
exposing multiple devices from a single server.

Co-authored-by: Diego Devesa <slarengh@gmail.com>
This commit is contained in:
Radoslav Gerganov 2025-10-07 09:59:13 +03:00 committed by GitHub
parent 0123ff38f5
commit c61ae20d05
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 41 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
tools/rpc/README.md
View File

@ -4,7 +4,7 @@
> This example and the RPC backend are currently in a proof-of-concept development stage. As such, the functionality is fragile and > This example and the RPC backend are currently in a proof-of-concept development stage. As such, the functionality is fragile and
> insecure. **Never run the RPC server on an open network or in a sensitive environment!** > insecure. **Never run the RPC server on an open network or in a sensitive environment!**
The `rpc-server` allows running `ggml` backend on a remote host. The `rpc-server` allows exposing `ggml` devices on a remote host.
The RPC backend communicates with one or several instances of `rpc-server` and offloads computations to them. The RPC backend communicates with one or several instances of `rpc-server` and offloads computations to them.
This can be used for distributed LLM inference with `llama.cpp` in the following way: This can be used for distributed LLM inference with `llama.cpp` in the following way:
@ -14,28 +14,34 @@ flowchart TD
rpcb<-->|TCP|srvb rpcb<-->|TCP|srvb
rpcb<-.->|TCP|srvn rpcb<-.->|TCP|srvn
subgraph hostn[Host N] subgraph hostn[Host N]
srvn[rpc-server]<-.->backend3["Backend (CUDA,Metal,etc.)"] srvn[rpc-server]<-.->dev4["CUDA0"]
srvn[rpc-server]<-.->dev5["CPU"]
end end
subgraph hostb[Host B] subgraph hostb[Host B]
srvb[rpc-server]<-->backend2["Backend (CUDA,Metal,etc.)"] srvb[rpc-server]<-->dev3["Metal"]
end end
subgraph hosta[Host A] subgraph hosta[Host A]
srva[rpc-server]<-->backend["Backend (CUDA,Metal,etc.)"] srva[rpc-server]<-->dev["CUDA0"]
srva[rpc-server]<-->dev2["CUDA1"]
end end
subgraph host[Main Host] subgraph host[Main Host]
local["Backend (CUDA,Metal,etc.)"]<-->ggml[llama-cli] local["Local devices"]<-->ggml[llama-cli]
ggml[llama-cli]<-->rpcb[RPC backend] ggml[llama-cli]<-->rpcb[RPC backend]
end end
style hostn stroke:#66,stroke-width:2px,stroke-dasharray: 5 5 style hostn stroke:#66,stroke-width:2px,stroke-dasharray: 5 5
classDef devcls fill:#5B9BD5
class local,dev,dev2,dev3,dev4,dev5 devcls
``` ```
Each host can run a different backend, e.g. one with CUDA and another with Metal. By default, `rpc-server` exposes all available accelerator devices on the host.
You can also run multiple `rpc-server` instances on the same host, each with a different backend. If there are no accelerators, it exposes a single `CPU` device.
## Usage ## Usage
On each host, build the corresponding backend with `cmake` and add `-DGGML_RPC=ON` to the build options. ### Remote hosts
For example, to build the CUDA backend with RPC support:
On each remote host, build the backends for each accelerator by adding `-DGGML_RPC=ON` to the build options.
For example, to build the `rpc-server` with support for CUDA accelerators:
```bash ```bash
mkdir build-rpc-cuda mkdir build-rpc-cuda
@ -44,33 +50,38 @@ cmake .. -DGGML_CUDA=ON -DGGML_RPC=ON
cmake --build . --config Release cmake --build . --config Release
``` ```
Then, start the `rpc-server` with the backend: When started, the `rpc-server` will detect and expose all available `CUDA` devices:
```bash ```bash
$ bin/rpc-server -p 50052 $ bin/rpc-server
create_backend: using CUDA backend
ggml_cuda_init: GGML_CUDA_FORCE_MMQ: no ggml_cuda_init: GGML_CUDA_FORCE_MMQ: no
ggml_cuda_init: CUDA_USE_TENSOR_CORES: yes ggml_cuda_init: GGML_CUDA_FORCE_CUBLAS: no
ggml_cuda_init: found 1 CUDA devices: ggml_cuda_init: found 1 CUDA devices:
Device 0: NVIDIA T1200 Laptop GPU, compute capability 7.5, VMM: yes Device 0: NVIDIA GeForce RTX 5090, compute capability 12.0, VMM: yes
Starting RPC server on 0.0.0.0:50052 Starting RPC server v3.0.0
endpoint : 127.0.0.1:50052
local cache : n/a
Devices:
CUDA0: NVIDIA GeForce RTX 5090 (32109 MiB, 31588 MiB free)
``` ```
When using the CUDA backend, you can specify the device with the `CUDA_VISIBLE_DEVICES` environment variable, e.g.: You can control the set of exposed CUDA devices with the `CUDA_VISIBLE_DEVICES` environment variable or the `--device` command line option. The following two commands have the same effect:
```bash ```bash
$ CUDA_VISIBLE_DEVICES=0 bin/rpc-server -p 50052 $ CUDA_VISIBLE_DEVICES=0 bin/rpc-server -p 50052
$ bin/rpc-server --device CUDA0 -p 50052
``` ```
This way you can run multiple `rpc-server` instances on the same host, each with a different CUDA device.
### Main host
On the main host build `llama.cpp` for the local backend and add `-DGGML_RPC=ON` to the build options. On the main host build `llama.cpp` with the backends for the local devices and add `-DGGML_RPC=ON` to the build options.
Finally, when running `llama-cli`, use the `--rpc` option to specify the host and port of each `rpc-server`: Finally, when running `llama-cli` or `llama-server`, use the `--rpc` option to specify the host and port of each `rpc-server`:
```bash ```bash
$ bin/llama-cli -m ../models/tinyllama-1b/ggml-model-f16.gguf -p "Hello, my name is" --repeat-penalty 1.0 -n 64 --rpc 192.168.88.10:50052,192.168.88.11:50052 -ngl 99 $ llama-cli -hf ggml-org/gemma-3-1b-it-GGUF -ngl 99 --rpc 192.168.88.10:50052,192.168.88.11:50052
``` ```
This way you can offload model layers to both local and remote devices. By default, llama.cpp distributes model weights and the KV cache across all available devices -- both local and remote -- in proportion to each device's available memory.
You can override this behavior with the `--tensor-split` option and set custom proportions when splitting tensor data across devices.
### Local cache ### Local cache
@ -83,3 +94,11 @@ $ bin/rpc-server -c
``` ```
By default, the cache is stored in the `$HOME/.cache/llama.cpp/rpc` directory and can be controlled via the `LLAMA_CACHE` environment variable. By default, the cache is stored in the `$HOME/.cache/llama.cpp/rpc` directory and can be controlled via the `LLAMA_CACHE` environment variable.
### Troubleshooting
Use the `GGML_RPC_DEBUG` environment variable to enable debug messages from `rpc-server`:
```bash
$ GGML_RPC_DEBUG=1 bin/rpc-server
```