Struct BufferPool 

pub struct BufferPool { /* private fields */ }

A pool of reusable, aligned buffers.

Buffers are organized into power-of-two size classes. When a buffer is requested, the smallest size class that fits is used. Buffers are automatically returned to the pool when dropped.

Alignment

Buffer alignment is guaranteed only at the base pointer (when cursor == 0). After calling Buf::advance(), the pointer returned by as_mut_ptr() may no longer be aligned. For direct I/O operations that require alignment, do not advance the buffer before use.

Implementations

impl BufferPool

pub fn alloc(&self, capacity: usize) -> IoBufMut

Allocates a buffer with the given capacity.

The returned buffer has len() == 0 and capacity() >= capacity, matching the semantics of IoBufMut::with_capacity and BytesMut::with_capacity. Use put_slice or other BufMut methods to write data to the buffer.

If the pool can provide a buffer (capacity within limits and pool not exhausted), returns a pooled buffer that will be returned to the pool when dropped. Otherwise, falls back to an untracked aligned heap allocation that is deallocated when dropped.

Use Self::try_alloc if you need to distinguish between pooled and untracked allocations.

Initialization

The returned buffer contains uninitialized memory. Do not read from it until data has been written.

pub fn try_alloc(&self, capacity: usize) -> Result<IoBufMut, PoolError>

Attempts to allocate a pooled buffer, returning an error on failure.

Unlike Self::alloc, this method does not fall back to untracked allocation. Use this when you need to know whether the buffer came from the pool.

Errors

• PoolError::Oversized: capacity exceeds max_size
• PoolError::Exhausted: Pool exhausted for required size class

pub fn config(&self) -> &BufferPoolConfig

Returns the pool configuration.

Trait Implementations

impl Clone for BufferPool

fn clone(&self) -> BufferPool

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for BufferPool

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

Formats the value using the given formatter.