Struct JemallocStats 

pub struct JemallocStats {
    pub allocated_bytes: u64,
    pub active_bytes: u64,
    pub metadata_bytes: u64,
    pub resident_bytes: u64,
    pub mapped_bytes: u64,
    pub retained_bytes: u64,
}

Snapshot of jemalloc’s process-wide accounting at one tick. All values are bytes. Definitions match the stats.* mallctl namespace (see jemalloc(3)).

Fields

allocated_bytes: u64

Bytes currently held by live application allocations (stats.allocated). The closest thing to “what is the live heap from the program’s point of view”. If this grows monotonically across runs while caches stay flat, the program is holding more memory.

active_bytes: u64

Bytes in active jemalloc extents (stats.active). Always >= allocated_bytes; the delta is fragmentation within active extents.

metadata_bytes: u64

Bytes used by jemalloc’s own metadata structures (stats.metadata).

resident_bytes: u64

jemalloc’s resident-set estimate (stats.resident): active + retained-but-resident + metadata, in pages.

mapped_bytes: u64

Total virtual memory mapped by jemalloc (stats.mapped).

retained_bytes: u64

Virtual memory retained by jemalloc after decommit (stats.retained). This is the bucket that explains “process RSS stays high after a workload finishes” — pages were returned to jemalloc but jemalloc has not yet returned them to the kernel. Controlled by dirty_decay_ms / muzzy_decay_ms in MALLOC_CONF.

Implementations

impl JemallocStats

pub fn observed_usage_bytes(self, process_bytes: u64) -> u64

Conservatively reconcile process-wide and allocator measurements.

These are overlapping views, so take their maximum rather than adding them or allowing a smaller allocator reading to hide other memory.

Trait Implementations

impl Clone for JemallocStats

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for JemallocStats

impl Debug for JemallocStats

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

Formats the value using the given formatter.

impl Default for JemallocStats

fn default() -> Self

Returns the “default value” for a type.

impl Eq for JemallocStats

impl PartialEq for JemallocStats

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for JemallocStats