Struct ProcessGroupStats 

#[non_exhaustive]
pub struct ProcessGroupStats {
    pub active_process_count: usize,
    pub total_cpu_time: Option<Duration>,
    pub peak_memory_bytes: Option<u64>,
}

Available on crate feature stats only.

A snapshot of a process group’s resource usage.

total_cpu_time and peak_memory_bytes are None when the platform can’t report them — notably the POSIX process-group mechanism (no cgroup accounting), i.e. macOS/BSD and the Linux fallback.

Non-exhaustive: a read-only snapshot the crate produces — new metrics can be added without a breaking change.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

active_process_count: usize

Number of live processes currently in the group.

Under the POSIX process-group mechanism (Mechanism::ProcessGroup — macOS/BSD and the Linux fallback) this counts live process groups rather than individual processes: a contained child that itself forks helpers still counts once. With a cgroup or Job Object it is the exact process count.

total_cpu_time: Option<Duration>

Total CPU time (user + kernel) accumulated by the group, if available.

Semantic divergence by backend:

• Windows Job Object — cumulative across all processes that have ever been part of the job, including already-terminated ones. Reflects the full historical cost of the tree.
• Linux cgroup v2 — sum of /proc/<pid>/stat times for currently live members only; terminated processes are not accounted once they leave the cgroup.
• POSIX process-group / macOS — always None; no kernel accumulator is available without a cgroup or Job Object.

peak_memory_bytes: Option<u64>

Peak memory used by the group in bytes, if available. This is the OS’s own group-wide measure; its exact meaning differs by platform and it is not directly comparable across platforms, nor equal to the sum of the per-process RunningProcess::peak_memory_bytes (which is a resident-set peak):

• Windows — the Job Object’s PeakJobMemoryUsed: peak committed memory (commit charge) charged to the job, not a working-set figure.
• Linux cgroup v2 — the sum of currently-live members’ peak resident sets (VmHWM); members that already exited are not counted.
• POSIX process-group / macOS — always None; no kernel accumulator.

Trait Implementations

impl Clone for ProcessGroupStats

fn clone(&self) -> ProcessGroupStats

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for ProcessGroupStats

impl Debug for ProcessGroupStats

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for ProcessGroupStats

impl PartialEq for ProcessGroupStats

fn eq(&self, other: &ProcessGroupStats) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for ProcessGroupStats