当KubeSchedulerConfiguration节点得分百分比设置为0时，将启用kubernetes 1.25中得调度程序默认行为.
默认行为是扫描50%的节点，该百分比减去集群中的节点数除以125（例如：2500个节点/125=20 =〉50% - 20个点=〉扫描30%的节点）。要扫描的最小节点为总数的5%或100个节点。
要完全理解调度程序的行为，请深入了解Kubernetes的源代码。

const (
    // SchedulerError is the reason recorded for events when an error occurs during scheduling a pod.
    SchedulerError = "SchedulerError"
    // Percentage of plugin metrics to be sampled.
    pluginMetricsSamplePercent = 10
    // minFeasibleNodesToFind is the minimum number of nodes that would be scored
    // in each scheduling cycle. This is a semi-arbitrary value to ensure that a
    // certain minimum of nodes are checked for feasibility. This in turn helps
    // ensure a minimum level of spreading.
    minFeasibleNodesToFind = 100
    // minFeasibleNodesPercentageToFind is the minimum percentage of nodes that
    // would be scored in each scheduling cycle. This is a semi-arbitrary value
    // to ensure that a certain minimum of nodes are checked for feasibility.
    // This in turn helps ensure a minimum level of spreading.
    minFeasibleNodesPercentageToFind = 5
)

// == trucated == //

// numFeasibleNodesToFind returns the number of feasible nodes that once found, the scheduler stops
// its search for more feasible nodes.
func (sched *Scheduler) numFeasibleNodesToFind(numAllNodes int32) (numNodes int32) {
    if numAllNodes < minFeasibleNodesToFind || sched.percentageOfNodesToScore >= 100 {
        return numAllNodes
    }

    adaptivePercentage := sched.percentageOfNodesToScore
    if adaptivePercentage <= 0 {
        basePercentageOfNodesToScore := int32(50)
        adaptivePercentage = basePercentageOfNodesToScore - numAllNodes/125
        if adaptivePercentage < minFeasibleNodesPercentageToFind {
            adaptivePercentage = minFeasibleNodesPercentageToFind
        }
    }

    numNodes = numAllNodes * adaptivePercentage / 100
    if numNodes < minFeasibleNodesToFind {
        return minFeasibleNodesToFind
    }

    return numNodes
}