Enum DwbMode 

pub enum DwbMode {
    Off,
    Buffered,
    Direct,
}

I/O mode for the double-write buffer file.

Variants

Off

DWB disabled — no torn-write protection. DoubleWriteBuffer::open returns None.

Buffered

Buffered I/O (page cache + fsync). Default when the parent WAL does not use O_DIRECT.

Direct

O_DIRECT I/O via an aligned buffer. The intended companion to an O_DIRECT WAL: keeps DWB bytes out of the page cache.

Implementations

impl DwbMode

pub fn default_for_parent(parent_uses_direct_io: bool) -> Self

Choose the DWB mode that mirrors the parent writer’s O_DIRECT setting when no explicit override is configured. With O_DIRECT on, the DWB should also be O_DIRECT, otherwise it undoes the cache-bypass.

Trait Implementations

impl Clone for DwbMode

fn clone(&self) -> DwbMode

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DwbMode

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

Formats the value using the given formatter.

impl PartialEq for DwbMode

fn eq(&self, other: &DwbMode) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for DwbMode

impl Eq for DwbMode

impl StructuralPartialEq for DwbMode