Struct rb_sys::tracking_allocator::TrackingAllocator

pub struct TrackingAllocator;

A simple wrapper over std::alloc::System which reports memory usage to the Ruby GC. This gives the GC a more accurate picture of the process’ memory usage so it can make better decisions about when to run.

Implementations

impl TrackingAllocator

pub const fn new() -> Self

Create a new TrackingAllocator.

pub const fn default() -> Self

Create a new TrackingAllocator with default values.

pub fn adjust_memory_usage(delta: isize) -> isize

Adjust the memory usage reported to the Ruby GC by delta. Useful for tracking allocations invisible to the Rust allocator, such as mmap or direct malloc calls.

Example

use rb_sys::TrackingAllocator;

// Allocate 1024 bytes of memory using `mmap` or `malloc`...
TrackingAllocator::adjust_memory_usage(1024);

// ...and then after the memory is freed, adjust the memory usage again.
TrackingAllocator::adjust_memory_usage(-1024);

Trait Implementations

impl Debug for TrackingAllocator

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

Formats the value using the given formatter.

impl GlobalAlloc for TrackingAllocator

unsafe fn alloc(&self, layout: Layout) -> *mut u8

Allocate memory as described by the given layout.

unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8

Behaves like alloc, but also ensures that the contents are set to zero before being returned.

unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout)

Deallocate the block of memory at the given ptr pointer with the given layout.

unsafe fn realloc( &self, ptr: *mut u8, layout: Layout, new_size: usize ) -> *mut u8

Shrink or grow a block of memory to the given new_size in bytes. The block is described by the given ptr pointer and layout.