Struct MemoryStats 

pub struct MemoryStats {

    pub current_mapped_bytes: usize,
    pub peak_mapped_bytes: usize,
    pub map_calls: usize,
    pub unmap_calls: usize,
    pub page_reset_calls: usize,
    pub page_reset_bytes: usize,
    pub guard_install_calls: usize,
    pub guard_install_bytes: usize,
    pub retained_free_segments: usize,
    pub max_retained_free_segments: usize,
    pub retained_free_bytes: usize,
    pub purged_segments: usize,
    pub purge_calls: usize,
    pub purged_bytes: usize,
    pub reset_segments: usize,
    pub reset_calls: usize,
    pub retained_huge_blocks: usize,
    pub retained_huge_bytes: usize,
    pub current_thread_live_allocations: usize,
    pub current_thread_owned_segments: usize,
    pub cross_thread_reclaimed_blocks: usize,
    pub page_refills: usize,
    pub recycled_pages: usize,
    pub fresh_pages: usize,
    pub fresh_segments: usize,
    pub orphan_segments_adopted: usize,
    pub recycle_sweeps: usize,
    pub size_class_occupancy: [SizeClassOccupancy; 52],
}

Snapshot of Mnemosyne memory mapping and segment cache state.

Fields

current_mapped_bytes: usize

Address space currently mapped from the OS, in bytes. Reserved space, not resident: a range stays counted after its physical backing is released, because the mapping is still held.

peak_mapped_bytes: usize

High-water mark of Self::current_mapped_bytes.

map_calls: usize

Successful map requests to the OS.

unmap_calls: usize

Successful unmap requests to the OS.

page_reset_calls: usize

Number of confirmed backend page_reset calls (Linux MADV_DONTNEED, macOS/FreeBSD MADV_FREE, Windows VirtualAlloc(MEM_RESET)).

page_reset_bytes: usize

Cumulative byte count passed to confirmed page_reset calls.

guard_install_calls: usize

Number of confirmed backend make_guard calls (Unix mprotect(PROT_NONE), Windows VirtualProtect(PAGE_NOACCESS)).

guard_install_bytes: usize

Cumulative byte count passed to confirmed make_guard calls.

retained_free_segments: usize

Free segments held in the cache for reuse instead of unmapped.

max_retained_free_segments: usize

Cap on Self::retained_free_segments; segments beyond it are purged rather than retained.

retained_free_bytes: usize

Bytes represented by the retained free segments.

purged_segments: usize

Segments returned to the OS by decay.

purge_calls: usize

Decay purge passes performed.

purged_bytes: usize

Bytes returned to the OS by those purges.

reset_segments: usize

Number of segments whose physical backing was released by a confirmed page_reset while the segment itself remained cached in the retained pool.

reset_calls: usize

Number of reset_segment_pool invocations.

retained_huge_blocks: usize

Number of huge blocks currently retained in the huge-allocation cache across all NUMA nodes.

retained_huge_bytes: usize

Total bytes of huge blocks currently retained in the huge-allocation cache across all NUMA nodes.

current_thread_live_allocations: usize

Allocations currently handed out by the calling thread.

current_thread_owned_segments: usize

Segments the calling thread owns and allocates from without coordination.

cross_thread_reclaimed_blocks: usize

Blocks freed by another thread and drained back into this thread’s pages.

page_refills: usize

Times a size class exhausted its page and acquired another; the sum of the three sources below.

recycled_pages: usize

Refills served from an already-held empty page, the cheapest outcome.

fresh_pages: usize

Refills that carved a new page from an owned segment.

fresh_segments: usize

Refills that needed a new segment, the only source reaching the OS backend.

orphan_segments_adopted: usize

Segments inherited from threads that exited still owning them, which keeps their memory reusable rather than stranded.

recycle_sweeps: usize

Decay-sweep passes over pages looking for empties to recycle.

Against Self::recycled_pages this shows whether sweeping is paying for itself or scanning without finding reusable pages.

size_class_occupancy: [SizeClassOccupancy; 52]

Per-size-class occupancy for the calling thread, indexed by size class.

Implementations

impl MemoryStats

pub fn to_json_with_bins(&self, bins: &[BinSnapshot]) -> String

Serializes this snapshot plus per-bin counters to a JSON string.

Use crate::stats::memory_stats_json for a convenient one-call version that captures the current stats automatically.

Trait Implementations

impl Clone for MemoryStats

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 MemoryStats

impl Debug for MemoryStats

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

Formats the value using the given formatter.

impl Default for MemoryStats

fn default() -> Self

Returns the “default value” for a type.

impl Eq for MemoryStats

impl PartialEq for MemoryStats

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for MemoryStats