Struct SearchStats 

pub struct SearchStats {

    pub node0_entries: u64,
    pub exit_tt_early: u64,
    pub exit_trivial: u64,
    pub exit_leaf: u64,
    pub exit_quick: u64,
    pub exit_later: u64,
    pub exit_tt_late: u64,
    pub reached_moveloop0: u64,
    pub tt_lookups: u64,
    pub tt_hits: u64,
    pub tt_stores: u64,
    pub cutoff_nodes: u64,
    pub allnode_nodes: u64,
    pub cutoff_first: u64,
    pub cutoff_index_sum: u64,
    pub cutoff_hist: [u64; 8],
}

Per-search instrumentation counters. All zero unless the crate is built with --features profiling. Two questions drive the layout — the same two that govern double-dummy speed:

1. TT hit rate — how often does a transposition-table probe prune an entire subtree? (tt_hits / tt_lookups)
2. Move ordering — when a node beta-cuts, how early in the move list does the cutoff fire? Perfect ordering cuts on move 1.

The node-0 funnel additionally attributes why lead nodes return without entering the move loop (TT, trivial bounds, quick/later tricks, leaf evaluation).

Fields

node0_entries: u64

Times Engine::ab_search_0 was entered.

exit_tt_early: u64

Returned via the depth >= 20 TT probe.

exit_trivial: u64

Returned via the trivial tricks_max bound checks.

exit_leaf: u64

Returned at the depth == 0 leaf evaluation.

exit_quick: u64

Returned because quick_tricks was decisive.

exit_later: u64

Returned because later_tricks_* was decisive.

exit_tt_late: u64

Returned via the depth < 20 TT probe.

reached_moveloop0: u64

Reached the move-generation + search loop.

tt_lookups: u64

Total tt_lookup calls.

tt_hits: u64

tt_lookup calls that returned a usable bound.

tt_stores: u64

tt.add stores from node 0.

cutoff_nodes: u64

Nodes whose move loop produced a beta/alpha cutoff.

allnode_nodes: u64

Nodes whose move loop ran to exhaustion without a cutoff.

cutoff_first: u64

Cutoffs that fired on the very first move tried.

cutoff_index_sum: u64

Sum of 1-based cutoff move indices (for the mean).

cutoff_hist: [u64; 8]

Histogram of 1-based cutoff index; the last bucket is “8+”.

Trait Implementations

impl Clone for SearchStats

fn clone(&self) -> SearchStats

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SearchStats

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

Formats the value using the given formatter.

impl Default for SearchStats

fn default() -> SearchStats

Returns the “default value” for a type.

impl Copy for SearchStats