Struct CompactOutcome 

pub struct CompactOutcome {
    pub selected: Vec<SegmentId>,
    pub still_referenced: Vec<SegmentId>,
    pub blocks_rewritten: usize,
    pub bytes_rewritten: u64,
    pub bytes_freed: u64,
    pub checkpoints: usize,
    pub attached: Option<CompactionAttached>,
    pub content_cno_before: Cno,
    pub content_cno_after: Cno,
    pub more_remaining: bool,
    pub dry_run: bool,
}

What a compaction pass did.

Fields

selected: Vec<SegmentId>

The objects whose live blocks were rewritten, ascending.

still_referenced: Vec<SegmentId>

Of those, the ones a walk taken afterwards still finds referenced. Empty on a pass that did what it set out to; anything here is an object that was not freed, and is reported rather than assumed away.

blocks_rewritten: usize

Blocks fs_relocate marked: what was done, not what was planned. A hole, an explicit zero block or a block already dirty is not counted.

bytes_rewritten: u64

bytes_freed: u64

The selected objects’ stored bytes — what prune can now reclaim.

checkpoints: usize

Checkpoints published: one for a pass that rewrote anything, none otherwise. That is how far last_cno advanced. Always none beside the writer, whose pass keeps the number: see attached.

attached: Option<CompactionAttached>

Beside the writer, what was attached: the version it was built on and the one it was attached to, the parts its objects are in, blocks moved, and how many conditional writes of the inode it took.

content_cno_before: Cno

fs_content_cno before and after the pass. Equal when consumers will not see the pass as a change of content, which is the ordinary case. They differ when the publish could not be marked: its number did not follow the previous one — an earlier flush failed and gave its number up — or the newest checkpoint was already a compaction and the pass ran anyway.

content_cno_after: Cno

more_remaining: bool

Whether the candidates outlasted the pass budget. Another pass would find more to do, at the cost of content_cno moving once (see CompactOptions::allow_consecutive).

dry_run: bool

Implementations

impl CompactOutcome

pub fn content_moved(&self) -> bool

Whether a consumer comparing content_cno will see this pass as a change.

Trait Implementations

impl Clone for CompactOutcome

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 CompactOutcome

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

Formats the value using the given formatter.

impl Default for CompactOutcome

fn default() -> Self

Returns the “default value” for a type.