Struct DirectFileRing 

pub struct DirectFileRing { /* private fields */ }

Non-mmap positioned-I/O ring with page-cache bypass.

Implementations

impl DirectFileRing

pub fn create( base_path: impl AsRef<Path>, capacity: usize, ) -> Result<Self, DirectFileError>

Obtain the ring at base_path over three files: {base}.directfile.data.bin (the slot array, unbuffered), {base}.directfile.head.bin (head counter, MMF), {base}.directfile.tail.bin (tail counter, MMF). Initializes them only where they do not yet exist, and otherwise attaches with queued slots and both counters in place. The data file carries no header, so capacity is checked against its exact byte size; a different capacity is a LayoutMismatch. reset reinitializes.

pub fn reset( base_path: impl AsRef<Path>, capacity: usize, ) -> Result<Self, DirectFileError>

Truncate the three files at base_path and initialize an empty ring, discarding queued slots live peers hold. For a caller that knows it owns the base path.

pub fn open( base_path: impl AsRef<Path>, expected_capacity: usize, ) -> Result<Self, DirectFileError>

Open an existing ring at base_path (a second process).

pub fn capacity(&self) -> usize

Capacity in slots.

pub fn head(&self) -> u64

Current head index.

pub fn tail(&self) -> u64

Current tail index.

pub fn try_push(&self, payload: &[u8]) -> Result<(), DirectFileError>

Push a payload: copy it into a page-aligned buffer and write it at the head’s slot offset with the page cache bypassed. Returns Err(Full) when head - tail == capacity.

pub fn try_pop(&self, out: &mut [u8]) -> Result<usize, DirectFileError>

Pop the oldest payload: read the tail’s slot into a page-aligned buffer (page cache bypassed), copy the relevant bytes to out, and advance the tail.

Trait Implementations

impl Drop for DirectFileRing

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl Send for DirectFileRing

impl Sync for DirectFileRing