Struct Report 

pub struct Report {
    pub high_cno: Cno,
    pub latest_compacted: bool,
    pub data_block_size: usize,
    pub meta_block_size: usize,
    pub objects: Vec<ObjectUsage>,
    pub out_of_range: usize,
    pub foreign_keys: usize,
    pub foreign_sample: Option<String>,
}

What a container’s storage is made of, and what could be given back.

Fields

high_cno: Cno

The checkpoint the walk was taken from.

latest_compacted: bool

Whether the newest published checkpoint is itself a compaction (InodeRaw::FLAG_COMPACTED). compact will not run on top of one unless asked to, since a second pass in a row moves content_cno.

data_block_size: usize

meta_block_size: usize

objects: Vec<ObjectUsage>

Objects whose checkpoint falls in the queried [low, high], ascending.

out_of_range: usize

Objects outside that range, which no operation here will touch.

foreign_keys: usize

Keys under the container’s prefix that are neither the inode nor a segment object. A WAL root nested under the container is the usual reason, and compaction refuses to run while any are present.

foreign_sample: Option<String>

Implementations

impl Report

pub fn bytes(&self) -> u64

Bytes stored by the objects in range.

pub fn bytes_live(&self) -> u64

Bytes still pointed into.

pub fn dead(&self) -> (usize, u64)

Objects nothing points into, and what they hold. This is prune’s work, and it needs no rewrite.

pub fn compactable(&self, max_live_ratio: f64) -> (usize, u64, u64)

What compaction at max_live_ratio would cost and free: (objects, bytes_to_rewrite, bytes_freed).

An estimate from the same numbers S3Cleaner::compact selects by, so a dry run and this agree. The bytes freed are the objects’ own, which prune collects afterwards; the rewrite itself publishes a new checkpoint holding the live blocks.

Trait Implementations

impl Clone for Report

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Report

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

Formats the value using the given formatter.