Struct VmMetrics 

pub struct VmMetrics {
    pub instructions_executed: u64,
    pub typed_trusted_ops: u64,
    pub typed_guarded_ops: u64,
    pub jit_dispatches: u64,
    pub interpreter_calls: u64,
    pub tier_events: RingBuffer<TierEvent, 256>,
    pub gc_pauses: RingBuffer<GcPauseEvent, 256>,
    pub gc_pause_histogram: Histogram,
    /* private fields */
}

Aggregated VM metrics with bounded memory usage.

When enabled on a [VirtualMachine], counters are bumped inline and events are pushed into fixed-size ring buffers. The structure is Option-wrapped in the VM so disabled metrics have zero per-instruction overhead.

Fields

instructions_executed: u64

Total bytecode instructions dispatched.

typed_trusted_ops: u64

Typed opcodes that ran without a guard check.

typed_guarded_ops: u64

Typed opcodes that required a runtime type guard.

jit_dispatches: u64

Calls dispatched through JIT-compiled code.

interpreter_calls: u64

Calls dispatched through the interpreter.

tier_events: RingBuffer<TierEvent, 256>

Recent tier transition events (last 256).

gc_pauses: RingBuffer<GcPauseEvent, 256>

Recent GC pause events (last 256).

gc_pause_histogram: Histogram

GC pause duration histogram.

Implementations

impl VmMetrics

pub fn new() -> Self

Create a fresh metrics collector.

pub fn record_instruction(&mut self)

pub fn record_trusted_op(&mut self)

pub fn record_guarded_op(&mut self)

pub fn record_jit_dispatch(&mut self)

pub fn record_interpreter_call(&mut self)

pub fn record_deopt_fallback(&mut self)

Record a deopt fallback (re-exec-from-entry) — should be rare in production.

pub fn record_tier_event(&mut self, event: TierEvent)

pub fn record_gc_pause(&mut self, event: GcPauseEvent)

pub fn elapsed_us(&self) -> u64

Microseconds elapsed since this metrics session started.

pub fn summary(&self) -> MetricsSummary

Compute a summary snapshot for logging / display.

Trait Implementations

impl Debug for VmMetrics

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

Formats the value using the given formatter.