Struct mz_persist_client::usage::ShardUsageAudit

pub struct ShardUsageAudit {
    pub current_state_batches_bytes: u64,
    pub current_state_rollups_bytes: u64,
    pub referenced_not_current_state_bytes: u64,
    pub not_leaked_not_referenced_bytes: u64,
    pub leaked_bytes: u64,
}

A breakdown of the size of various contributions to a shard’s blob (S3) usage.

This is structured as a “funnel”, in which the steps are additive. Specifically 1=2a+2b, 2a=3a+3b, 3a=4a+4b, 4a=5a+5b (so the “a“s are the funnel and the “b“s are places where data splits out of the funnel).

Fields

current_state_batches_bytes: u64

5a: Data in batches/parts referenced by the most recent version of state.

current_state_rollups_bytes: u64

5b: Data in rollups referenced by the most recent version of state.

referenced_not_current_state_bytes: u64

4b: Data referenced by a live version of state that is not the most recent.

Possible causes:

• SeqNo hold
• Waiting for a GC run

not_leaked_not_referenced_bytes: u64

3b: Data not referenced by any live version of state.

Possible causes:

• A batch or rollup that’s about to be linked into state
• A batch leaked by a crash, but the writer has not yet been force expired
• A rollup leaked by a crash, but GC has not yet advanced past the SeqNo

leaked_bytes: u64

2b: Data that is eligible for reclamation by a (future) leaked blob cleanup task (database-issues#5018).

Possible causes:

• A batch or rollup written by a process which crashed (or was rolled) before it could be linked into state.

Implementations

impl ShardUsageAudit

pub fn current_state_bytes(&self) -> u64

4a: Data referenced by the most recent version of state.

pub fn referenced_bytes(&self) -> u64

3a: Data referenced by any live version of state.

pub fn not_leaked_bytes(&self) -> u64

2a: Data that would not be reclaimed by a (future) leaked blob cleanup task (database-issues#5018).

pub fn total_bytes(&self) -> u64

1: Raw blob (S3) usage.

NB: Due to race conditions between reads of blob and consensus in the usage code, this might be a slight under-counting.

Trait Implementations

impl Clone for ShardUsageAudit

fn clone(&self) -> ShardUsageAudit

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ShardUsageAudit

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

Formats the value using the given formatter.

impl Display for ShardUsageAudit

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

Formats the value using the given formatter.

impl<T: Debug> From<ShardUsageCumulativeMaybeRacy<'_, T>> for ShardUsageAudit

fn from(x: ShardUsageCumulativeMaybeRacy<'_, T>) -> Self

Converts to this type from the input type.