Struct rb_sys::tracking_allocator::ManuallyTracked

pub struct ManuallyTracked<T> { /* private fields */ }

A guard which adjusts the memory usage reported to the Ruby GC by delta. This allows you to track resources which are invisible to the Rust allocator, such as items that are known to internally use mmap or direct malloc in their implementation.

Internally, it uses an Arc<AtomicIsize> to track the memory usage delta, and is safe to clone when T is Clone.

Example

use rb_sys::tracking_allocator::ManuallyTracked;

type SomethingThatUsedMmap = ();

// Will tell the Ruby GC that 1024 bytes were allocated.
let item = ManuallyTracked::new(SomethingThatUsedMmap, 1024);

// Will tell the Ruby GC that 1024 bytes were freed.
std::mem::drop(item);

Implementations

impl<T> ManuallyTracked<T>

pub fn wrap(item: T, memsize: usize) -> Self

Create a new ManuallyTracked<T>, and immediately report that memsize bytes were allocated.

pub fn increase_memory_usage(&self, memsize: usize)

Increase the memory usage reported to the Ruby GC by memsize bytes.

pub fn decrease_memory_usage(&self, memsize: usize)

Decrease the memory usage reported to the Ruby GC by memsize bytes.

pub fn memsize_delta(&self) -> isize

Get the current memory usage delta.

pub fn get(&self) -> &T

Get a shared reference to the inner T.

pub fn get_mut(&mut self) -> &mut T

Get a mutable reference to the inner T.

impl ManuallyTracked<()>

pub fn new(memsize: usize) -> Self

Create a new ManuallyTracked<()>, and immediately report that memsize bytes were allocated.

Trait Implementations

impl<T: Clone> Clone for ManuallyTracked<T>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for ManuallyTracked<T>

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

Formats the value using the given formatter.

impl Default for ManuallyTracked<()>

fn default() -> Self

Returns the “default value” for a type.