Enum StorageTier 

#[non_exhaustive]
pub enum StorageTier {
    L0Ram,
    L1Nvme,
    L2Remote,
}

Storage tier classification.

Data flows downward: L0 → L1 → L2 as it ages and cools.

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.

L0Ram

L0 (Hot): Lock-free radix trees, memtables, active CRDT states. Pure RAM — no I/O.

L1Nvme

L1 (Warm): HNSW graphs, metadata indexes, segment files. NVMe via mmap + madvise(MADV_WILLNEED). Zero-copy deserialization, SIMD reads directly from mmap.

L2Remote

L2 (Cold): Historical logs, compressed vector layers. Remote object storage (S3/GCS), Parquet-encoded. DataFusion predicate pushdown for minimal egress.

Implementations

impl StorageTier

pub fn is_memory_resident(self) -> bool

Whether this tier is memory-resident (no I/O needed).

pub fn uses_mmap(self) -> bool

Whether this tier uses mmap (potential page faults on TPC cores).

pub fn is_remote(self) -> bool

Whether this tier requires network I/O.

Trait Implementations

impl Clone for StorageTier

fn clone(&self) -> StorageTier

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StorageTier

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

Formats the value using the given formatter.

impl PartialEq for StorageTier

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

impl Eq for StorageTier

impl StructuralPartialEq for StorageTier