const envRebalanceWorkers = "_MINIO_REBALANCE_WORKERS"
	workerSize, err := env.GetInt(envRebalanceWorkers, len(pool.sets))
	if err != nil {
		rebalanceLogIf(ctx, fmt.Errorf("invalid workers value err: %v, defaulting to %d", err, len(pool.sets)))
		workerSize = len(pool.sets)
	}

	// Each decom worker needs one List() goroutine/worker
	// add that many extra workers.
	workerSize += len(pool.sets)

const (
	transitionWorkers = "transition_workers"
	expirationWorkers = "expiration_workers"
	// EnvILMTransitionWorkers env variable to configure number of transition workers
	EnvILMTransitionWorkers = "MINIO_ILM_TRANSITION_WORKERS"
	// EnvILMExpirationWorkers env variable to configure number of expiration workers
	EnvILMExpirationWorkers = "MINIO_ILM_EXPIRATION_WORKERS"
)

var (
	defaultHelpPostfix = func(key string) string {

	es := newExpiryState(context.Background(), objAPI, 0)
	workers := []chan expiryOp{make(chan expiryOp)}
	es.workers.Store(&workers)
	globalExpiryState = es
	var wg sync.WaitGroup
	wg.Add(1)
	expired := make([]ObjectToDelete, 0, 5)
	go func() {
		defer wg.Done()
		workers := globalExpiryState.workers.Load()
		for t := range (*workers)[0] {
			if t, ok := t.(newerNoncurrentTask); ok {

		config.HelpKV{
			Key:         apiReplicationMaxWorkers,
			Description: `set the maximum number of replication workers` + defaultHelpPostfix(apiReplicationMaxWorkers),
			Optional:    true,
			Type:        "number",
		},
		config.HelpKV{
			Key:         apiTransitionWorkers,
			Description: `set the number of transition workers` + defaultHelpPostfix(apiTransitionWorkers),
			Optional:    true,
			Type:        "number",
		},

			Optional:    true,
			Type:        "int",
		},
		config.HelpKV{
			Key:         DriveWorkers,
			Description: `the number of workers per drive to heal a new disk replacement` + defaultHelpPostfix(DriveWorkers),
			Optional:    true,
			Type:        "int",
		},
	}

	totalFailedCount    MetricName = "total_failed_count"
	totalFailedBytes    MetricName = "total_failed_bytes"

	currActiveWorkers  MetricName = "current_active_workers"
	avgActiveWorkers   MetricName = "average_active_workers"
	maxActiveWorkers   MetricName = "max_active_workers"
	recentBacklogCount MetricName = "recent_backlog_count"
	currInQueueCount   MetricName = "last_minute_queued_count"

	for len(p.workers) < n {
		input := make(chan ReplicationWorkerOperation, 10000)
		p.workers = append(p.workers, input)

		go p.AddWorker(input, &p.activeWorkers)
	}
	for len(p.workers) > n {
		worker := p.workers[len(p.workers)-1]
		p.workers = p.workers[:len(p.workers)-1]
		xioutil.SafeClose(worker)
	}
}

// ResizeWorkerPriority sets replication failed workers pool size

	sync.RWMutex                 // mutex for Cache
	mostRecentStatsMu sync.Mutex // mutex for mostRecentStats

	wlock sync.RWMutex // mutex for active workers

	movingAvgTicker *time.Ticker // Ticker for calculating moving averages
	wTimer          *time.Ticker // ticker for calculating active workers
	qTimer          *time.Ticker // ticker for calculating queue stats
}

func (r *ReplicationStats) trackEWMA() {
	for {
		select {

		workers = workers[:len(workers)-1]
		worker <- expiryOp(nil)
		es.stats.workers.Add(-1)
	}
	// Atomically replace workers.
	es.workers.Store(&workers)
}

// Worker handles 4 types of expiration tasks.
// 1. Expiry of objects, includes regular and transitioned objects
// 2. Expiry of noncurrent versions due to NewerNoncurrentVersions

	current      [][]string       // current block of results to be returned
	recordsRead  int              // number of records read in current slice
	input        chan *queueItem  // input for workers
	queue        chan *queueItem  // output from workers in order
	err          error            // global error state, only touched by Reader.Read
	bufferPool   sync.Pool        // pool of []byte objects for input