Struct Accounting 

struct Accounting {
    totals: Arc<Totals>,
    logging: Option<ChannelLogging>,
}

Running totals over the buffer’s contents, plus the introspection logging that reports them.

Shared by the buffer and by every structure that holds its chains, so the totals are maintained where chains are minted and retired rather than by a walk over the buffer.

Correctness rests on a discipline the code already keeps for the introspection logging: a chain the buffer holds has been announced exactly once through Accounting::chain_created, and is retired exactly once, through Accounting::chain_dropped, before it is dropped or consumed. Chains are immutable once announced, so the totals a chain contributes at retirement are the ones it contributed at announcement. metrics_totals_match_walk checks the result against a walk.

Fields

totals: Arc<Totals>

The totals, shared with every clone.

logging: Option<ChannelLogging>

Introspection logging, absent when the sink is not logging.

Implementations

impl Accounting

fn new(logging: Option<ChannelLogging>) -> Self

Construct accounting that reports to the given logging, if any.

fn totals(&self) -> (usize, SizeMetrics)

Return the current totals as (records, size metrics).

The reported capacity equals the size: chunk bodies are exactly sized when minted, and the staging vector’s slack is bounded by one chunk’s worth of updates and not tracked.

fn chain_created<D: Data>(&self, chain: &Chain<D>)

Account for a chain the buffer now holds.

fn chain_dropped<D: Data>(&self, chain: &Chain<D>)

Account for a chain the buffer no longer holds.

fn stage_created(&self)

Announce the staging area as an empty chain, which is how its population is reported.

fn stage_dropped(&self, records: usize, bytes: usize, allocations: usize)

Retire the staging area, which holds records updates, bytes bytes, and allocations allocations.

Balances Accounting::stage_created: the chain the stage is reported as is dropped at its current length.

fn stage_diff(&self, records: isize, bytes: isize, allocations: isize)

Account for the staging area changing by records updates, bytes bytes, and allocations allocations.

fn report_size_metrics(&self, new: SizeMetrics, old: SizeMetrics)

Report the change from old to new size metrics to introspection.

Trait Implementations

impl Clone for Accounting

fn clone(&self) -> Accounting

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Accounting

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

Formats the value using the given formatter.