Eldric Docs 5.0.198 ← eldric.ai
Inference

Splitting a model across machines

Status · Administrators · Applies to 5.0.194

Eldric cannot yet run one model across several machines. Every model is served whole by one node: on its graphics card, partly in system memory, or on the processor. This page says what you can do today with a model too large for any one card, and what we measured about splitting one.

What to do today

  • Run the model on a node whose card and system memory together hold it. A model that does not fit the card loads partly on the processor, and a Mixture-of-Experts model keeps its layers on the card and moves only expert weights out (Mixture-of-experts models).
  • Use a smaller quantisation of the same model.
  • Serve the model from a cloud provider through the cloud module (Cloud provider keys).

Several nodes can each serve their own models to the whole cluster; that is described on Models across the cluster, and it is a different thing from splitting one model.

What we measured

This is a measurement, not a feature. On 2026-10-30 RESEARCH split one model by layers across two of our nodes with llama.cpp's own tools, outside Eldric, to find out whether such a split is fast enough to chat with.

Measured: one model split by layers across two nodes A measurement, not a feature. A 14-billion-parameter model (Qwen2.5-14B, Q8_0, 15.7 GB) fits on neither card alone. Its layers were divided by free memory between node A, with a 12 GB card, and node B, with an 8 GB card, joined by a 1 Gbit link. The model answered at 27.8 tokens per second, the first token after 0.56 s for a 512-token prompt. The link carried about 15 Mbit/s. Splitting inside every layer instead was 12 times slower. Measured on 2026-10-30 with upstream llama.cpp tools, outside Eldric. Measurement, 2026-10-30, upstream llama.cpp tools. Not in any Eldric release Node A 12 GB graphics card part of the layers prompt and answer start here Node B 8 GB graphics card the rest of the layers 1 Gbit link ~15 Mbit/s used Qwen2.5-14B Q8_0, 15.7 GB fits on neither card alone 27.8 tok/s answer speed 0.56 s first token, 512-token prompt 12× slower splitting inside each layer
Measured on 2026-10-30 with upstream llama.cpp tools. Not part of any Eldric release.
RunModelWherePrompt, tokens/sAnswer, tokens/s
controlQwen2.5-7B Q4_K_Mone node, 12 GB card7001100.0
split by layerssametwo nodes, half the layers each137681.6
split inside each layersametwo nodes67.66.9
split by layersQwen2.5-14B Q8_0, 15.7 GBtwo nodes, 12 GB and 8 GB cards91427.8
  • The 14B model fits on neither card alone. Split by layers it answered at 27.8 tokens per second, and the first token of an answer to a 512-token prompt came after 0.56 s (2.1 s for 2048 tokens).
  • Splitting costs most when reading the prompt: the 7B model read prompts at a fifth of its single-node speed and answered at 82 % of it.
  • The nodes were joined by 1 Gbit. The 14B split used about 15 Mbit/s of it; what limits it is the number of round trips, not the bandwidth.
  • Splitting inside every layer instead of between layers was 12 times slower when answering. Over 1 Gbit it is not usable.

What the measurement does not say

It says that a 14B model split over two consumer cards on 1 Gbit was fast enough to chat with, on that pair of machines, with that build. It says nothing about more than two nodes or about several requests at once. And it does not mean Eldric can do it: no Eldric release can split a model, and we do not give a date. The upstream project calls the transport these tools use insecure, so for the measurement it was reachable only from the two test machines and was removed afterwards.