Crate mimalloc_pprof 

Rust global allocator support for the in-tree mimalloc build.

use mimalloc_pprof::{prof, MiMalloc};
#[global_allocator] static ALLOCATOR: MiMalloc = MiMalloc;
prof::start(512 * 1024);
prof::dump_file(std::path::Path::new("heap.prof"))?;

Profiling is enabled by default. To build the allocator without profiler hooks, depend on this crate with default-features = false; in that mode the profiling API remains available but cannot start a profiler.

See the README’s Rust integration guide for frame-pointer and line-table build flags. Open the resulting profile with pprof -http=: app.exe heap.prof.

Modules

dhat

Exact DHAT v2 heap/lifetime profiling controls.

memory_events

Opt-in allocation-change accounting and callbacks (include/mimalloc/memory-events.h).

options

mimalloc’s mi_option_* settings: the runtime knobs behind every MIMALLOC_* environment variable.

prof

Safe controls for mimalloc’s sampled heap profiler.

stats

The allocator’s own exact statistics, as opposed to the sampled numbers crate::prof::stats reports.

sys

Raw bindings to the in-tree mimalloc static amalgamation.

Structs

IdlePark

Returned by park_while_idle; ends the park when dropped.

MiMalloc

A #[global_allocator] implementation backed by mimalloc.

ProfConfig

Ergonomic, Rust-facing sibling of mi_prof_config_t (include/mimalloc/profile.h) for enable_heap_profiling_with.

Enums

DumpFormat

Output format for ProfConfig::dump_at_exit.

ProfConfigMode

How ProfConfig fields interact with the profiler’s environment variables and mi_option_* settings.

Functions

enable_heap_profiling

Turn on sampled heap profiling at the default sample rate.

enable_heap_profiling_with

Turn on sampled heap profiling using a struct-based configuration.

expand^⚠

Try to grow an allocation in place, without moving it.

heap_dump_json

Live per-heap -> per-page -> (optional) per-block JSON snapshot of the current subprocess (issue #269, Bun parity P4). Backs Bun’s shipped bun:jsc heapStats({dump:true|"blocks"}).mimallocDump; see src/heap-dump.c for the JSON shape ({"heaps":[{"seq":N,"pages":[{"id","block_size","used","reserved","thread_id"}], "blocks":[[id,size],...]}]}, blocks present only when include_blocks).

on_thread_idle

Tell mimalloc this thread is idle (issue #272, Bun parity P7a).

park_while_idle

Guard form of on_thread_idle for a thread that is about to BLOCK: hands this thread’s heaps to the background scavenger, which does the idle work above while this thread sits in the kernel, and takes them back on drop.

purge_holes_report

Print, per size class, what hole purging leaves behind (issue #272, Bun parity P7b).

purge_holes_stats

What page hole purging has reclaimed, process wide (issue #272, Bun parity P7b).

recalloc^⚠

Grow or shrink an allocation to count * size bytes, zeroing any newly-exposed tail.

rezalloc^⚠

Grow or shrink an allocation, zeroing any newly-exposed tail.

scavenger_stop

Stop the background scavenger thread (issue #272).

unwrapped_free^⚠

Free a pointer returned by unwrapped_malloc or unwrapped_realloc.

unwrapped_malloc^⚠

Allocate size bytes from mimalloc’s raw-OS-layer “unwrapped” path.

unwrapped_realloc^⚠

Resize a pointer returned by unwrapped_malloc or unwrapped_realloc.

usable_size^⚠

Bytes actually available in an allocation, which may exceed what was requested.