/// <summary>
/// Worker method that actually computes and updates the statistic.
/// </summary>
private void DoSetEarlyStopMoveSecondaryFlags()
{
if (Manager.Root.NumChildrenExpanded == 0)
{
return;
}
float aggressiveness = Context.ParamsSearch.MoveFutilityPruningAggressiveness;
if (aggressiveness > 1.0f)
{
throw new Exception("Ceres configuration error: maximum value of EarlyStopMoveSecondaryAggressiveness is 1.0.");
}
float MIN_BEST_N_FRAC_REQUIRED = ManagerChooseRootMove.MIN_FRAC_N_REQUIRED_MIN(Context);
// Calibrate aggressiveness such that :
// - at maximum value of 1.0 we assume 50% visits go to second best move(s)
// - at reasonable default value 0.5 we assume 75% of visits to go second best move(s)
float aggressivenessMultiplier = 1.0f / (1.0f - aggressiveness * 0.5f);
int?numRemainingSteps = Manager.EstimatedNumVisitsRemaining();
// Can't make any determiniation if we can't estimate how many steps left
if (numRemainingSteps is null)
{
return;
}
int numStepsTotal = (int)(numRemainingSteps / Manager.FractionSearchRemaining);
MCTSNode[] nodesSortedN = Root.ChildrenSorted(n => - n.N);
MCTSNode bestNNode = nodesSortedN[0];
int minN = Root.N / 5;// (int)(bestQNode.N * MIN_BEST_N_FRAC_REQUIRED);
MCTSNode[] nodesSortedQ = Root.ChildrenSorted(n => n.N < minN ? int.MaxValue : (float)n.Q);
MCTSNode bestQNode = nodesSortedQ[0];
float bestQ = (float)bestQNode.Q;
ManagerChooseRootMove bestMoveChoser = new(Context.Root, false, Context.ParamsSearch.MLHBonusFactor);
Span <MCTSNodeStructChild> children = Root.Ref.Children;
for (int i = 0; i < Root.Ref.NumChildrenExpanded; i++)
{
// Never shut down second best move unless the whole search is eligible to shut down
if (nodesSortedN.Length > 1)
{
MCTSNode secondBestMove = Context.ParamsSearch.BestMoveMode == ParamsSearch.BestMoveModeEnum.TopN ? nodesSortedN[1] : nodesSortedQ[1];
bool isSecondBestMove = children[i].Move == secondBestMove.PriorMove;
if (isSecondBestMove && !Context.ParamsSearch.FutilityPruningStopSearchEnabled)
{
Context.RootMovesArePruned[i] = false;
continue;
}
}
float earlyStopGapRaw;
if (Context.ParamsSearch.BestMoveMode == ParamsSearch.BestMoveModeEnum.TopN)
{
earlyStopGapRaw = nodesSortedN[0].N - children[i].N;
}
else
{
int minNRequired = (int)(bestQNode.N * MIN_BEST_N_FRAC_REQUIRED);
earlyStopGapRaw = minNRequired - children[i].N;
}
float earlyStopGapAjusted = earlyStopGapRaw * aggressivenessMultiplier;
bool earlyStopSimple = earlyStopGapRaw > numRemainingSteps;
if (MCTSDiagnostics.DumpSearchFutilityShutdown &&
earlyStopSimple &&
!Context.RootMovesArePruned[i] &&
NumberOfNotShutdownChildren() < 3)
{
Console.WriteLine();
Console.WriteLine($"\r\nShutdown {children[i].Move} [{children[i].N}] at root N {Context.Root.N} with remaning {numRemainingSteps}"
+ $" due to raw gapN {earlyStopGapRaw} adusted to {earlyStopGapAjusted} in mode {Context.ParamsSearch.BestMoveMode} aggmult {aggressivenessMultiplier}");
DumpDiagnosticsMoveShutdown();
}
Context.RootMovesArePruned[i] = earlyStopSimple;
// Console.WriteLine(i + $" EarlyStopMoveSecondary(simple) gap={gapToBest} adjustedGap={inflatedGap} remaining={numRemainingSteps} ");
}
// TODO: log this
//Console.WriteLine($"{Context.RemainingTime,5:F2}sec remains at N={Root.N}, setting minN to {minN} number still considered {count} " +
// $"using EstimatedNPS {Context.EstimatedNPS} with nodes remaining {Context.EstimatedNumStepsRemaining()} " +
// statsStr);
}
/// <summary>
/// Worker method that actually computes and updates the statistic.
/// </summary>
private void DoSetEarlyStopMoveSecondaryFlags()
{
if (Manager.Root.NumChildrenExpanded == 0)
{
return;
}
float aggressiveness = Context.ParamsSearch.MoveFutilityPruningAggressiveness;
if (aggressiveness >= 1.5f)
{
throw new Exception("Ceres configuration error: maximum value of EarlyStopMoveSecondaryAggressiveness is 1.5.");
}
float MIN_BEST_N_FRAC_REQUIRED = ManagerChooseRootMove.MIN_FRAC_N_REQUIRED_MIN;
// Calibrate aggressiveness such that :
// - at maximum value of 1.0 we assume 50% visits go to second best move(s)
// - at reasonable default value 0.5 we assume 75% of visits to go second best move(s)
float aggressivenessMultiplier = 1.0f / (1.0f - aggressiveness * 0.5f);
int?numRemainingSteps = Manager.EstimatedNumVisitsRemaining();
// Can't make any determiniation if we can't estimate how many steps left
if (numRemainingSteps is null)
{
return;
}
int numStepsTotal = (int)(numRemainingSteps / Manager.FractionSearchRemaining);
MCTSNode[] nodesSortedN = Root.ChildrenSorted(n => - n.N);
MCTSNode bestNNode = nodesSortedN[0];
int minN = Root.N / 5;// (int)(bestQNode.N * MIN_BEST_N_FRAC_REQUIRED);
MCTSNode[] nodesSortedQ = Root.ChildrenSorted(n => n.N < minN ? int.MaxValue : (float)n.Q);
MCTSNode bestQNode = nodesSortedQ[0];
float bestQ = (float)bestQNode.Q;
ManagerChooseRootMove bestMoveChoser = new(Context.Root, false, Context.ParamsSearch.MLHBonusFactor);
Span <MCTSNodeStructChild> children = Root.Ref.Children;
for (int i = 0; i < Root.Ref.NumChildrenExpanded; i++)
{
// Never shut down second best move unless the whole search is eligible to shut down
if (nodesSortedN.Length > 1)
{
MCTSNode secondBestMove = Context.ParamsSearch.BestMoveMode == ParamsSearch.BestMoveModeEnum.TopN ? nodesSortedN[1] : nodesSortedQ[1];
bool isSecondBestMove = children[i].Move == secondBestMove.PriorMove;
if (isSecondBestMove &&
!Context.ParamsSearch.FutilityPruningStopSearchEnabled &&
Context.RootMovesPruningStatus[i] != MCTSFutilityPruningStatus.PrunedDueToSearchMoves)
{
Context.RootMovesPruningStatus[i] = MCTSFutilityPruningStatus.NotPruned;
continue;
}
}
float earlyStopGapRaw;
if (Context.ParamsSearch.BestMoveMode == ParamsSearch.BestMoveModeEnum.TopN)
{
earlyStopGapRaw = nodesSortedN[0].N - children[i].N;
}
else
{
int minNRequired = (int)(bestQNode.N * MIN_BEST_N_FRAC_REQUIRED);
earlyStopGapRaw = minNRequired - children[i].N;
}
float earlyStopGapAdjusted = earlyStopGapRaw * aggressivenessMultiplier;
bool earlyStop = earlyStopGapAdjusted > numRemainingSteps;
if (Context.RootMovesPruningStatus[i] == MCTSFutilityPruningStatus.NotPruned && earlyStop)
{
#if NOT_HELPFUL
// Never shutdown nodes getting large fraction of all visits
float fracVisitsThisMoveRunningAverage = Context.RootMoveTracker != null ? Context.RootMoveTracker.RunningFractionVisits[i] : 0;
const float THRESHOLD_VISIT_FRACTION_DO_NOT_SHUTDOWN_CHILD = 0.20f;
bool shouldVeto = (fracVisitsThisMoveRunningAverage > THRESHOLD_VISIT_FRACTION_DO_NOT_SHUTDOWN_CHILD);
if (Context.ParamsSearch.TestFlag &&
nodesSortedN[0] != Context.Root.ChildAtIndex(i) &&
NumberOfNotShutdownChildren() > 1 &&
shouldVeto)
{
MCTSEventSource.TestCounter1++;
continue;
}
else
#endif
Context.RootMovesPruningStatus[i] = MCTSFutilityPruningStatus.PrunedDueToFutility;
if (MCTSDiagnostics.DumpSearchFutilityShutdown)
{
Console.WriteLine();
Console.WriteLine($"\r\nShutdown {children[i].Move} [{children[i].N}] at root N {Context.Root.N} with remaning {numRemainingSteps}"
+ $" due to raw gapN {earlyStopGapRaw} adusted to {earlyStopGapAdjusted} in mode {Context.ParamsSearch.BestMoveMode} aggmult {aggressivenessMultiplier}");
DumpDiagnosticsMoveShutdown();
}
}
// Console.WriteLine(i + $" EarlyStopMoveSecondary(simple) gap={gapToBest} adjustedGap={inflatedGap} remaining={numRemainingSteps} ");
}
// TODO: log this
//Console.WriteLine($"{Context.RemainingTime,5:F2}sec remains at N={Root.N}, setting minN to {minN} number still considered {count} " +
// $"using EstimatedNPS {Context.EstimatedNPS} with nodes remaining {Context.EstimatedNumStepsRemaining()} " +
// statsStr);
}
