Module device_selection 

PCI topology parsing and device discovery utilities for RDMA device selection.

ibverbs-specific selection logic lives in crate::backend::ibverbs::device_selection.

Structs

PCIAddress

A PCI address, e.g. 0000:07:00.0, as found under /sys/bus/pci/devices.

PciPath

A classified path between two PCI endpoints: its PathType and the bottleneck (minimum) PCIe link bandwidth along it, in MB/s.

Enums

MemoryLocation

A source of memory for a transfer. A None index means “any device of this kind”: the location is then ranked against the best of all CPU nodes or all GPUs.

PathType

Locality of a path between two PCI endpoints, ordered best to worst. A path’s type is its worst (least local) segment.

Functions

cpu_path

Path from CPU memory to the device at addr. With a specific NUMA node, the device is PathType::Phb when it sits on that node and PathType::Sys otherwise; with None (any CPU) it is judged against its own node and so is always PathType::Phb. Bandwidth is the device’s PCIe chain bottleneck.

get_cuda_pci_address

PCI address of the CUDA device with ordinal idx, read from /proc/driver/nvidia/gpus/*/information (the NVIDIA driver keys each GPU’s bus id there by its device minor, which equals the CUDA ordinal).

pci_path

The PathType and bottleneck bandwidth of the PCIe path between two PCI endpoints.