Struct MvccClock 

pub struct MvccClock { /* private fields */ }

Process-wide logical clock. Cheap to clone — internally an Arc over an AtomicU64 in the Database wiring (added in Phase 11.3). Standalone today.

Implementations

impl MvccClock

pub fn new(initial: u64) -> Self

Builds a clock seeded at initial. The next MvccClock::tick returns initial + 1.

Use this with the value persisted in the WAL header at open time so the clock resumes past the last-checkpointed high-water mark.

pub fn now(&self) -> u64

Returns the current high-water timestamp without advancing it. Phase 11.6’s GC reads this alongside super::ActiveTxRegistry::min_active_begin_ts to decide which row-version chains are reclaimable.

pub fn tick(&self) -> u64

Bumps the clock by one and returns the new value. Strictly monotonic: every call observes a distinct u64.

pub fn observe(&self, value: u64)

Promotes the clock to at least value. No-op if value is at or below the current high-water mark. Used at WAL replay to bring the in-memory clock up to the persisted high-water without an extra tick().

Trait Implementations

impl Debug for MvccClock

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

Formats the value using the given formatter.

impl Default for MvccClock

fn default() -> MvccClock

Returns the “default value” for a type.