Enum EngineId 

pub enum EngineId {
    Vector,
    Graph,
    DocumentSchemaless,
    DocumentStrict,
    Kv,
    Columnar,
    Timeseries,
    Spatial,
    Array,
    Fts,
    Sparse,
    Crdt,
    Query,
    Wal,
    Bridge,
}

Identifies a subsystem that owns a memory budget.

Each engine operates within its allocated memory ceiling. The governor tracks allocations per engine and rejects requests that would exceed the budget.

Covers all eight peer engines (Document schemaless, Document strict, KV, Columnar, Timeseries, Spatial, Vector, Array), plus the two cross-engine overlays (Graph, Fts), plus infrastructure subsystems (Sparse metadata, Crdt, Query, Wal, Bridge).

Variants

Vector

HNSW vector index, distance computation buffers, quantized caches.

Graph

CSR adjacency index, traversal algorithm working sets (cross-engine overlay).

DocumentSchemaless

Document (schemaless): MessagePack blobs, secondary index buffers.

DocumentStrict

Document (strict): Binary Tuple encode/decode buffers, schema metadata.

Kv

Key-Value engine: hash index buckets, TTL expiry wheel.

Columnar

Columnar engine: compressed segment build buffers, block statistics.

Timeseries

Gorilla-encoded memtables, Zstd dictionaries, log buffers.

Spatial

R*-tree node pools, geohash / H3 index structures.

Array

Array engine (ND sparse): tile decompression buffers, coordinate arrays.

Fts

FTS LSM memtable, posting lists, compaction merge buffers (cross-engine overlay).

Sparse

redb B-Tree, splintr inverted index, schema metadata (sparse/metadata engine).

Crdt

loro CRDT state, merge buffers, operation logs.

Query

DataFusion query execution: sorts, aggregates, hash tables.

Wal

WAL write buffers, group commit staging.

Bridge

SPSC bridge buffers, slab allocator, envelope staging.

Implementations

impl EngineId

pub const ALL: &'static [EngineId]

All known engine identifiers (for iteration in the governor).

Trait Implementations

impl Clone for EngineId

fn clone(&self) -> EngineId

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EngineId

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

Formats the value using the given formatter.

impl Display for EngineId

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

Formats the value using the given formatter.

impl Hash for EngineId

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for EngineId

fn eq(&self, other: &EngineId) -> 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 EngineId

impl Eq for EngineId

impl StructuralPartialEq for EngineId