Struct HostMeshShutdownGuard 

pub struct HostMeshShutdownGuard(pub HostMesh);

Wrapper around HostMesh that runs shutdown on Drop.

Tuple Fields

0: HostMesh

Methods from Deref<Target = HostMesh>

pub async fn shutdown(&mut self, cx: &impl Actor) -> Result<()>

Request a clean shutdown of all hosts owned by this HostMesh.

Uses a two-phase approach:

1. Terminate children on every host concurrently. Service infrastructure (host agent, comm proc, networking) stays alive so that forwarder flushes can still reach remote hosts.
2. Shut down hosts concurrently. No user procs remain, so this is fast and cannot deadlock on cross-host flush timeouts.

pub async fn stop(&mut self, cx: &impl Actor) -> Result<()>

Stop all hosts owned by this HostMesh, draining user procs but keeping worker processes and their sockets alive for reconnection.

After stop, the same worker addresses can be passed to HostMesh::attach to create a new mesh.

pub fn set_bootstrap(&mut self, cmd: BootstrapCommand)

Set the bootstrap command on the underlying HostMeshRef, so that future spawn calls use it. Unlike HostMeshRef::with_bootstrap this mutates in place, preserving ownership.

Methods from Deref<Target = HostMeshRef>

pub async fn spawn<C: Actor>( &self, cx: &C, name: &str, per_host: Extent, proc_bind: Option<Vec<ProcBind>>, per_rank_bootstrap: Option<Box<PerRankBootstrapFn>>, ) -> Result<ProcMesh>

where C::A: Handler<MeshFailure>,

Spawn a ProcMesh onto this host mesh. The per_host extent specifies the shape of the procs to spawn on each host.

proc_bind, when provided, is a per-process CPU/NUMA binding configuration. Its length must equal the number of ranks in per_host. Each entry maps binding keys (cpunodebind, membind, physcpubind, cpus) to their values. Only takes effect when running on Linux.

per_rank_bootstrap, when provided, is a function called once per proc to produce that proc’s BootstrapCommand. The function receives a view::Point over the combined host_extent ⊕ per_host extent. Its return value takes precedence over self.bootstrap_command for that proc only.

Currently, spawn issues direct calls to each host agent. This will be fixed by maintaining a comm actor on the host service procs themselves.

pub fn id(&self) -> &HostMeshId

The identity of the referenced host mesh.

pub fn hosts(&self) -> &[HostRef]

The host references (channel addresses) in rank order.

Trait Implementations

impl Deref for HostMeshShutdownGuard

type Target = HostMesh

The resulting type after dereferencing.

fn deref(&self) -> &HostMesh

Dereferences the value.

impl DerefMut for HostMeshShutdownGuard

fn deref_mut(&mut self) -> &mut HostMesh

Mutably dereferences the value.

impl Drop for HostMeshShutdownGuard

fn drop(&mut self)

Best-effort cleanup for owned host meshes on drop.

When a HostMesh is dropped, it attempts to shut down all hosts it owns:

• If a Tokio runtime is available, we spawn an ephemeral Proc + Instance and send ShutdownHost messages to each host. This ensures that the embedded BootstrapProcManagers are dropped, and all child procs they spawned are killed.
• If no runtime is available, we cannot perform async cleanup here; in that case we log a warning and rely on kernel-level PDEATHSIG or the individual BootstrapProcManager’s Drop as the final safeguard.

This path is last resort: callers should prefer explicit HostMesh::shutdown to guarantee orderly teardown. Drop only provides opportunistic cleanup to prevent process leaks if shutdown is skipped.