// diskFillFraction is the fraction of a disk we allow to be filled.
	diskFillFraction = 0.99

	// diskReserveFraction is the fraction of a disk where we will fill other server pools first.
	// If all pools reach this, we will use all pools with regular placement.
	diskReserveFraction = 0.15

	// diskAssumeUnknownSize is the size to assume when an unknown size upload is requested.
	diskAssumeUnknownSize = 1 << 30

version: v1
address: ':9000'
console-address: ':9001'
certs-dir: '/home/user/.minio/certs/'
pools: # Specify the nodes and drives with pools
  -
        - 'https://server-example-pool1:9000/mnt/disk1/'
        - 'https://server1-pool1:9000/mnt/disk{1...4}/'
        - 'https://server3-pool1:9000/mnt/disk{1...4}/'
        - 'https://server4-pool1:9000/mnt/disk{1...4}/'
  -
        - 'https://server-example-pool2:9000/mnt/disk{1...4}/'

version: v1
address: ':9000'
console-address: ':9001'
certs-dir: '/home/user/.minio/certs/'
pools: # Specify the nodes and drives with pools
  -
        - 'https://server-example-pool1:9000/mnt/disk{1...4}/'
        - 'https://server{1...2}-pool1:9000/mnt/disk{1...4}/'
        - 'https://server3-pool1:9000/mnt/disk{1...4}/'
        - 'https://server4-pool1:9000/mnt/disk{1...4}/'
  -
        - 'https://server-example-pool2:9000/mnt/disk{1...4}/'

docker volume rm $(docker volume ls -q -f dangling=true) || true

# Stop two nodes, one of each pool, to check that all S3 calls work while quorum is still there
[ "${MODE}" == "pools" ] && docker-compose -f minio-${MODE}.yaml stop minio2
[ "${MODE}" == "pools" ] && docker-compose -f minio-${MODE}.yaml stop minio6

# Pause one node, to check that all S3 calls work while one node goes wrong

   * is complete. It does so by using daemon threads and adding a shutdown hook to wait for their
   * completion.
   *
   * <p>This is mainly for fixed thread pools. See {@link Executors#newFixedThreadPool(int)}.
   *
   * @param executor the executor to modify to make sure it exits when the application is finished

	if err != nil {
		return err
	}
	setDriveCount := uint64(v)

	var pools []poolArgs
	switch cv.Version {
	case "v1":
		cfV1 := config.ServerConfigV1{}
		if err = yaml.Unmarshal(rd, &cfV1); err != nil {
			return err
		}

		pools = make([]poolArgs, 0, len(cfV1.Pools))
		for _, list := range cfV1.Pools {
			pools = append(pools, poolArgs{
				args:          list,
				setDriveCount: setDriveCount,
			})

	w := c.tabwriter()
	zDump := c.ztunnelDump

	pols := slices.Filter(zDump.Policies, filter.Verify)
	slices.SortFunc(pols, func(a, b *ZtunnelPolicy) int {
		if r := cmp.Compare(a.Namespace, b.Namespace); r != 0 {
			return r
		}
		return cmp.Compare(a.Name, b.Name)
	})
	fmt.Fprintln(w, "NAMESPACE\tPOLICY NAME\tACTION\tSCOPE")

	for _, pol := range pols {
		fmt.Fprintf(w, "%v\t%v\t%v\t%v\n",

package schema

import (
	"reflect"
	"sync"
)

// sync pools
var (
	normalPool      sync.Map
	poolInitializer = func(reflectType reflect.Type) FieldNewValuePool {
		v, _ := normalPool.LoadOrStore(reflectType, &sync.Pool{
			New: func() interface{} {
				return reflect.New(reflectType).Interface()
			},
		})
		return v.(FieldNewValuePool)
	}

	if peer == "" {
		return nil
	}

	var pools []int
	for _, ep := range l {
		for _, endpoint := range ep.Endpoints {
			if endpoint.IsLocal {
				continue
			}

			if !slices.Contains(pools, endpoint.PoolIdx) {
				pools = append(pools, endpoint.PoolIdx)
			}
		}
	}

	return pools
}

- MinIO also supports expansion of existing clusters in server pools. Each pool is a self contained entity with same SLA's (read/write quorum) for each object as original cluster. By using the existing namespace for lookup validation MinIO ensures conflicting objects are not created. When no such object exists then MinIO simply uses the least used pool to place new objects.

### There are no limits on how many server pools can be combined

```