Struct ArenaWriteSet 

pub struct ArenaWriteSet { /* private fields */ }

MVCC write-set using 128-bit fingerprints instead of Vec

Memory Comparison

Structure	Per-entry Memory	1000 entries
HashSet<Vec>	24 + heap (~50B)	~74 KB
HashSet	16 bytes	16 KB
Savings	~70%	~58 KB

Operations

• Insert: O(1) with no allocation
• Contains: O(1) with pre-computed hash
• is_disjoint: O(min(n,m)) where n,m are set sizes

Implementations

impl ArenaWriteSet

pub fn new() -> Self

Create a new empty write set

pub fn with_capacity(capacity: usize) -> Self

Create with expected capacity

pub fn insert(&mut self, fingerprint: KeyFingerprint) -> bool

Insert a key fingerprint

pub fn insert_bytes(&mut self, key: &[u8]) -> bool

Insert from raw bytes

pub fn contains(&self, fingerprint: &KeyFingerprint) -> bool

Check if a key is in the write set

pub fn contains_bytes(&self, key: &[u8]) -> bool

Check if write set contains key by bytes

pub fn is_disjoint(&self, other: &ArenaWriteSet) -> bool

Check if two write sets are disjoint (no common keys)

pub fn len(&self) -> usize

Get the number of keys in the write set

pub fn is_empty(&self) -> bool

Check if the write set is empty

pub fn iter(&self) -> impl Iterator<Item = &KeyFingerprint>

Iterate over fingerprints

pub fn clear(&mut self)

Clear the write set

Trait Implementations

impl Default for ArenaWriteSet

fn default() -> Self

Returns the “default value” for a type.