Struct CheckpointStats 

pub struct CheckpointStats {
    pub total_count: u64,
    pub last_write_us: u64,
    pub last_sync_us: u64,
    pub last_total_us: u64,
    pub last_wal_bytes: u64,
    pub last_snapshot_bytes: u64,
    pub last_files_synced: u32,
    pub recent_total_us: VecDeque<u64>,
}

v7.37.13 (A1.9) — per-checkpoint instrumentation. PG-equivalent of LogCheckpointEnd, with [PG+] percentile buckets over a rolling window of recent checkpoints (PG just logs the latest).

All durations are microseconds. Fields below “last_*” describe the most recent checkpoint; “total_count” counts every successful checkpoint over the process lifetime. The recent_total_us deque holds up to CHECKPOINT_STATS_WINDOW total-duration samples for p50/p95/p99 computation.

Fields

total_count: u64

Process-lifetime count of successful checkpoints. Failed (poisoned, IO error) checkpoints do NOT advance this.

last_write_us: u64

Snapshot serialize + tmp+rename duration (µs).

last_sync_us: u64

WAL flush_now + chunk rotation duration (µs).

last_total_us: u64

End-to-end checkpoint duration (µs) = write + manifest + sync + rotate.

last_wal_bytes: u64

Bytes of WAL that fell behind the marker (= WAL written during this checkpoint, roughly).

last_snapshot_bytes: u64

Snapshot bytes written to disk.

last_files_synced: u32

Files synced as part of the checkpoint (snapshot + manifest

• WAL marker + dir fsyncs). Approximate — counts the major disk touches, not every internal sync_data() call.

recent_total_us: VecDeque<u64>

[PG+] Rolling window of last_total_us for percentile computation. Oldest at front, newest at back; bounded at CHECKPOINT_STATS_WINDOW.

Implementations

impl CheckpointStats

pub fn percentiles(&self) -> (u64, u64, u64)

[PG+] p50 / p95 / p99 of recent_total_us. Returns (p50, p95, p99) in microseconds. If the window has fewer than 3 samples each value is the last observed sample.

Trait Implementations

impl Clone for CheckpointStats

fn clone(&self) -> CheckpointStats

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CheckpointStats

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

Formats the value using the given formatter.

impl Default for CheckpointStats

fn default() -> CheckpointStats

Returns the “default value” for a type.