Enum CompressionMode 

#[non_exhaustive]
pub enum CompressionMode {
    Off,
    Lz4,
}

Phase 3 (issue #8): per-pager compression knob. Selects whether newly-created files use the transparent LZ4 page-compression layer (format_minor = 1, feature_flags bit 0 set) or stay at the original uncompressed format_minor = 0 layout.

No-op against existing files: when a pager opens an already-initialised database, the file’s own header dictates whether compression is in use; this knob only affects file creation.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Off

Default — newly-created files use format_minor = 0 with the full 32-bit CRC32C per-page trailer (no compression).

Lz4

Newly-created files use format_minor = 1 with LZ4 page compression. Requires the compression Cargo feature on obj-core / obj-db. A build WITHOUT that feature refuses to open any format_minor >= 1 file with Error::FormatFeatureUnsupported.

Trait Implementations

impl Clone for CompressionMode

fn clone(&self) -> CompressionMode

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CompressionMode

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

Formats the value using the given formatter.

impl Default for CompressionMode

fn default() -> CompressionMode

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for CompressionMode

fn deserialize<__D>( __deserializer: __D, ) -> Result<CompressionMode, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for CompressionMode

fn eq(&self, other: &CompressionMode) -> 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 Serialize for CompressionMode

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for CompressionMode

impl Eq for CompressionMode

impl StructuralPartialEq for CompressionMode