Struct ExecutionSummaryCounts 

pub struct ExecutionSummaryCounts {
    pub iops: usize,
    pub requests: usize,
    pub bytes_read: usize,
    pub indices_loaded: usize,
    pub parts_loaded: usize,
    pub index_comparisons: usize,
    pub all_counts: HashMap<String, usize>,
    pub all_times: HashMap<String, usize>,
}

Fields

iops: usize

The number of I/O operations performed

requests: usize

The number of requests made to the storage layer (may be larger or smaller than iops depending on coalescing configuration)

bytes_read: usize

The number of bytes read during the execution of the plan

indices_loaded: usize

The number of top-level indices loaded

parts_loaded: usize

The number of index partitions loaded

index_comparisons: usize

The number of index comparisons performed (the exact meaning depends on the index type)

all_counts: HashMap<String, usize>

Additional metrics for more detailed statistics. These are subject to change in the future and should only be used for debugging purposes.

Newer metrics (e.g. INDEX_CACHE_HITS_METRIC, INDEX_CACHE_MISSES_METRIC) are added here rather than as pub fields, so this struct stays backwards compatible for callers that construct or destructure it. Prefer the typed accessors below.

all_times: HashMap<String, usize>

Additional time metrics for more detailed statistics, stored in nanoseconds. These are subject to change in the future and should only be used for debugging purposes.

Implementations

impl ExecutionSummaryCounts

pub fn index_cache_hits(&self) -> usize

Number of index cache page lookups where the loader was not executed (per-page granularity).

A “hit” is any page-level lookup at an instrumented cache boundary that did not run the loader on this call. That covers both a true cache hit on an already-populated entry and a coalesced concurrent load where an in-flight loader started by a different caller produced the value.

Instrumented boundaries in this release: BTree page, IVF partition (v2, write_cache=true scan path), inverted posting list (grouped and per-token), inverted per-token metadata (PostingMetadataKey), inverted phrase positions (PositionKey), bitmap posting (Equals / Range / IsIn), ngram posting, and rtree page / null slot.

Caveats:

• IVF v2 streaming scans and legacy v1 IVF partitions run load_partition with write_cache=false. Those loads always execute the loader and never write the result back, so they are reported as a miss on every call. See Self::index_cache_hit_ratio.
• A cold posting-list lookup on the grouped inverted layout can record up to two misses (posting-list group + per-token metadata) for a single term.

Other index cache boundaries such as HNSW graph pages and quantizer codebooks are not yet instrumented; a scan that only touches those paths returns 0 here.

pub fn index_cache_misses(&self) -> usize

Number of index cache page lookups that had to execute the loader (per-page granularity).

A “miss” is any page-level lookup at an instrumented cache boundary where the loader ran, i.e. the page was not resident and had to be materialised (typically from storage). See Self::index_cache_hits for the paired counter and the list of instrumented boundaries.

pub fn index_cache_hit_ratio(&self) -> f32

Ratio of index cache hits to total lookups. Returns 0.0 when no lookups were recorded in this scan.

This ratio only reflects paths that write their result back to the index cache. Streaming scans (IVF v2 write_cache=false and legacy v1 IVF load_partition_stream) intentionally bypass the cache and are counted as misses on every call, so a workload dominated by streaming vector scans will report a hit ratio near 0.0 regardless of cache size.

Trait Implementations

impl Clone for ExecutionSummaryCounts

fn clone(&self) -> ExecutionSummaryCounts

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExecutionSummaryCounts

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

Formats the value using the given formatter.

impl Default for ExecutionSummaryCounts

fn default() -> ExecutionSummaryCounts

Returns the “default value” for a type.

impl Eq for ExecutionSummaryCounts

impl PartialEq for ExecutionSummaryCounts

fn eq(&self, other: &ExecutionSummaryCounts) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ExecutionSummaryCounts