Struct StringInterner 

pub struct StringInterner { /* private fields */ }

A thread-safe interner that deduplicates strings into Arc<str>.

Internally backed by a DashMap which provides lock-free concurrent reads with per-shard locking for writes, eliminating the global RwLock contention bottleneck.

Example

use chronix_engine::memtable::interner::StringInterner;

let interner = StringInterner::new();
let a = interner.intern("cpu");
let b = interner.intern("cpu");
assert!(std::sync::Arc::ptr_eq(&a, &b));

Implementations

impl StringInterner

pub fn new() -> Self

Create an empty interner.

pub fn intern(&self, s: &str) -> Arc<str>

Intern a string, returning a shared Arc<str>.

If the string has been seen before, the existing Arc is cloned (lock-free read via DashMap shard). Otherwise, a new Arc<str> is allocated and inserted (per-shard write lock only).

pub fn lookup(&self, s: &str) -> Option<Arc<str>>

Look up a previously interned string without inserting.

Returns Some(Arc<str>) if the string was already interned, None otherwise.

pub fn len(&self) -> usize

Number of unique strings interned.

pub fn is_empty(&self) -> bool

Returns true if no strings have been interned.

pub fn memory_bytes(&self) -> usize

Approximate heap bytes held by the interner.

The interned strings themselves plus the map’s per-entry overhead: an Arc<str> header (two usize counts), the fat pointer the map stores, and a hash slot. Interned strings are tag keys, tag values and measurement names, so on a high-cardinality workload this is the term that grows, and on the gateway it is one of the three that the memtable budget does not count.

Trait Implementations

impl Debug for StringInterner

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

Formats the value using the given formatter.

impl Default for StringInterner

fn default() -> Self

Returns the “default value” for a type.