Struct PosixBackend 

pub struct PosixBackend { /* private fields */ }

Implementations

impl PosixBackend

pub fn new(layout: Layout) -> Result<Self>

pub fn layout(&self) -> &Layout

impl PosixBackend

pub fn drop_pagecache(&self)

2026-09-25: Advise the kernel to drop every layer file’s page cache (POSIX_FADV_DONTNEED), so later reads go to the device. A no-op on non-unix targets, where reads may still come from the cache.

Trait Implementations

impl StorageBackend for PosixBackend

fn read(&mut self, requests: &[ReadRequest], stream: u64) -> Result<()>

2026-09-25: Fill every request’s destination. Returns once the data is in place, so work the caller enqueues on stream afterwards reads it.

fn write_from_host(&mut self, key: GroupKey, src: &[u8]) -> Result<()>

2026-09-25: Write one group from host memory; src is group_bytes() long.

fn group_layout(&self) -> GroupLayout

2026-09-25: The geometry the default block methods fan out with.

fn read_async(&mut self, requests: &[ReadRequest], stream: u64) -> Result<()>

2026-09-25: Like read, but an implementation may return before the copies on stream finish. The default calls read.

fn read_blocks( &mut self, requests: &[BlockReadRequest], stream: u64, ) -> Result<()>

2026-09-25: Read whole blocks, with the stream contract of read. The default fans out to read through expand_blocks_to_groups.

fn read_blocks_async( &mut self, requests: &[BlockReadRequest], stream: u64, ) -> Result<()>

2026-09-25: The block form of read_async. The default fans out to read_async.

fn write_block_from_host( &mut self, base_key: GroupKey, src: &[u8], ) -> Result<()>

2026-09-25: Write one whole block. src is block_bytes() laid out [K0, …, K(nkv-1), V0, …, V(nkv-1)] at group_stride pitch; only base_key’s layer and block are read. The default rejects any other length, then calls write_from_host for K(kh) and V(kh) of each head.

fn write_blocks_run( &mut self, base_key: GroupKey, run_len: usize, src: &[u8], ) -> Result<()>

2026-09-25: Write run_len consecutive blocks of one layer, starting at base_key’s block; src is run_len · block_bytes(). The default rejects any other length, then calls write_block_from_host once per block.

fn supports_write_run_coalescing(&self) -> bool

2026-09-25: Whether this backend serves write_blocks_run as one wide op. The default is false.

fn register_landing_region(&mut self, base: u64, len: usize) -> Result<()>

2026-09-25: Register [base, base + len) as the region reads land in. The RDMA backends register it as one memory region per rail; the default does nothing.