Struct mz_adapter::coord::in_memory_oracle::InMemoryTimestampOracle

pub struct InMemoryTimestampOracle<T, N>
where
    T: Debug,
    N: GenericNowFn<T>,
{
    read_ts: T,
    write_ts: T,
    next: N,
}

A type that provides write and read timestamps, reads observe exactly their preceding writes.

Specifically, all read timestamps will be greater or equal to all previously reported completed write timestamps, and strictly less than all subsequently emitted write timestamps.

A timeline can perform reads and writes. Reads happen at the read timestamp and writes happen at the write timestamp. After the write has completed, but before a response is sent, the read timestamp must be updated to a value greater than or equal to self.write_ts.

Fields

read_ts: T

write_ts: T

next: N

Implementations

impl<T: TimestampManipulation, N> InMemoryTimestampOracle<T, N>

where N: GenericNowFn<T>,

pub fn new(initially: T, next: N) -> Self

where N: GenericNowFn<T>,

Create a new timeline, starting at the indicated time. next generates new timestamps when invoked. The timestamps have no requirements, and can retreat from previous invocations.

fn write_ts(&mut self) -> WriteTimestamp<T>

Acquire a new timestamp for writing.

This timestamp will be strictly greater than all prior values of self.read_ts() and self.write_ts().

fn peek_write_ts(&self) -> T

Peek the current write timestamp.

pub(crate) fn read_ts(&self) -> T

Acquire a new timestamp for reading.

This timestamp will be greater or equal to all prior values of self.apply_write(write_ts), and strictly less than all subsequent values of self.write_ts().

pub(crate) fn apply_write(&mut self, write_ts: T)

Mark a write at write_ts completed.

All subsequent values of self.read_ts() will be greater or equal to write_ts.

Trait Implementations

impl<T, N> Debug for InMemoryTimestampOracle<T, N>

where T: Debug + Debug, N: GenericNowFn<T>,

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

Formats the value using the given formatter.