Struct MultiGpuCoordinator 

pub struct MultiGpuCoordinator {
    config: MultiGpuConfig,
    devices: RwLock<Vec<DeviceInfo>>,
    kernel_device_map: RwLock<HashMap<KernelId, usize>>,
    device_kernel_counts: RwLock<Vec<AtomicUsize>>,
    round_robin_counter: AtomicUsize,
    total_kernels: AtomicU64,
    custom_selector: RwLock<Option<Arc<dyn Fn(&[DeviceStatus], &LaunchOptions) -> usize + Send + Sync>>>,
    topology: RwLock<Option<GpuTopology>>,
}

Multi-GPU coordinator for managing kernels across devices.

Fields

config: MultiGpuConfig

Configuration.

devices: RwLock<Vec<DeviceInfo>>

Available devices.

kernel_device_map: RwLock<HashMap<KernelId, usize>>

Kernel-to-device mapping.

device_kernel_counts: RwLock<Vec<AtomicUsize>>

Device kernel counts.

round_robin_counter: AtomicUsize

Round-robin counter.

total_kernels: AtomicU64

Total kernels launched.

custom_selector: RwLock<Option<Arc<dyn Fn(&[DeviceStatus], &LaunchOptions) -> usize + Send + Sync>>>

Device selection callbacks (for custom strategy).

topology: RwLock<Option<GpuTopology>>

GPU topology graph.

Implementations

impl MultiGpuCoordinator

pub fn new(config: MultiGpuConfig) -> Arc<Self>

Create a new multi-GPU coordinator.

pub fn register_device(&self, device: DeviceInfo)

Register a device with the coordinator.

pub fn unregister_device(&self, index: usize) -> DeviceUnregisterResult

Unregister a device and plan kernel migrations.

This method:

1. Identifies all kernels on the device being removed
2. Finds target devices for each kernel using load balancing
3. Creates migration plans for kernels that can be moved
4. Marks orphaned kernels that have no migration target
5. Updates internal routing tables

The caller is responsible for executing the actual migrations using KernelMigrator with the returned KernelMigrationPlan entries.

fn select_migration_target(&self, candidates: &[usize]) -> Option<usize>

Select the best target device for migration.

fn calculate_migration_priority( &self, _kernel_id: &KernelId, ) -> MigrationPriority

Calculate migration priority for a kernel.

pub fn devices(&self) -> Vec<DeviceInfo>

Get all registered devices.

pub fn device(&self, index: usize) -> Option<DeviceInfo>

Get device info by index.

pub fn device_count(&self) -> usize

Get number of devices.

pub fn select_device(&self, options: &LaunchOptions) -> Result<usize>

Select a device for launching a kernel.

pub fn assign_kernel(&self, kernel_id: KernelId, device_index: usize)

Assign a kernel to a device.

pub fn remove_kernel(&self, kernel_id: &KernelId)

Remove a kernel assignment.

pub fn get_kernel_device(&self, kernel_id: &KernelId) -> Option<usize>

Get device for a kernel.

pub fn kernels_on_device(&self, device_index: usize) -> Vec<KernelId>

Get all kernels on a device.

pub fn get_all_status(&self) -> Vec<DeviceStatus>

Get status of all devices.

pub fn get_device_status(&self, device_index: usize) -> Option<DeviceStatus>

Get status of a specific device.

pub fn set_custom_selector<F>(&self, selector: F)

where F: Fn(&[DeviceStatus], &LaunchOptions) -> usize + Send + Sync + 'static,

Set custom device selector.

pub fn stats(&self) -> MultiGpuStats

Get coordinator statistics.

pub fn can_p2p(&self, device_a: usize, device_b: usize) -> bool

Check if P2P is available between two devices.

pub fn update_device_memory(&self, device_index: usize, available_memory: u64)

Update device memory info.

pub fn discover_topology(&self) -> GpuTopology

Discover GPU topology (estimates if probing not available).

pub fn topology(&self) -> GpuTopology

Get current topology (discovers if not cached).

pub fn set_topology(&self, topology: GpuTopology)

Set custom topology (for testing or manual configuration).

pub fn select_device_for_k2k(&self, source_kernel: &KernelId) -> Result<usize>

Get best device for communicating with a source kernel.

pub fn request_migration( &self, kernel_id: &KernelId, target_device: usize, ) -> Result<MigrationRequest>

Request to migrate a kernel to another device.

pub fn complete_migration(&self, request: &MigrationRequest) -> Result<()>

Complete a migration (updates internal mappings).