howtospark
Training

Partial layer offload

Offload / distributeOffloadingReference

Pin the first N layers on the GPU and run the rest from host RAM (llama.cpp --n-gpu-layers, accelerate device_map).

On the Spark

The commodity path when a model just barely overflows GPU memory on a discrete-GPU box; on unified Spark memory it's moot.

Objective
Offload / distribute
Relieves
Capacity
Targets
Weights
Format
Static GPU/CPU layer split
Granularity
Per-layer (N layers on GPU, rest on host)
Lifecycle
PTQ · no gradients
Calibration
No calibration
Compression
None — relocates, doesn't shrink
Quality
100% — same weights, bit-exact
Hardware
Host RAM for the offloaded layers; PCIe bandwidth bounds decode
Runtimes
llama.cppTransformers

A worked Spark recipe for this method hasn't been written yet — it lives here as a reference point in the ontology.