}
	sys.Unlock()
}

// RemoveStaleBuckets removes all stale buckets in memory that are not on disk.
func (sys *BucketMetadataSys) RemoveStaleBuckets(diskBuckets set.StringSet) {
	sys.Lock()
	defer sys.Unlock()

	for bucket := range sys.metadataMap {
		if diskBuckets.Contains(bucket) {
			continue
		} // doesn't exist on disk remove from memory.
		delete(sys.metadataMap, bucket)
		globalBucketMonitor.DeleteBucket(bucket)
	}

	ahs.healStatus[tracker.ID] = t
	tracker.mu.RUnlock()
}

// Sort by zone, set and disk index
func sortDisks(disks []madmin.Disk) {
	sort.Slice(disks, func(i, j int) bool {
		a, b := &disks[i], &disks[j]
		if a.PoolIndex != b.PoolIndex {
			return a.PoolIndex < b.PoolIndex
		}
		if a.SetIndex != b.SetIndex {
			return a.SetIndex < b.SetIndex
		}

package disk

import (
	"errors"
	"fmt"
	"os"
	"syscall"
	"unsafe"

	"golang.org/x/sys/windows"
)

var (
	kernel32 = windows.NewLazySystemDLL("kernel32.dll")

	// GetDiskFreeSpaceEx - https://msdn.microsoft.com/en-us/library/windows/desktop/aa364937(v=vs.85).aspx
	// Retrieves information about the amount of space that is available on a disk volume,

// (st_size, as made by say ftruncate(2)), would require a metadata flush.
//
// The aim of fdatasync() is to reduce disk activity for applications that
// do not require all metadata to be synchronized with the disk.
func Fdatasync(f *os.File) error {
	return syscall.Fdatasync(int(f.Fd()))
}

// FadviseDontNeed invalidates page-cache
func FadviseDontNeed(f *os.File) error {

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package ioutil

import (
	"io"
	"io/fs"
	"os"

	"github.com/minio/minio/internal/disk"
)

var (
	// OpenFileDirectIO allows overriding default function.
	OpenFileDirectIO = disk.OpenFileDirectIO
	// OsOpen allows overriding default function.
	OsOpen = os.Open
	// OsOpenFile allows overriding default function.
	OsOpenFile = os.OpenFile
)

# limitations under the License.
# ==============================================================================
# Sourcing this enables local disk cache
if [[ $(uname -s) == "Darwin" ]]; then
  echo "Please note that using disk cache on macOS is not recommended because the"
  echo "cache can end up being pretty big and make the build process inefficient."
fi

echo -n "Starting MinIO instances ..."
minio server --certs-dir /tmp/certs --address ":9001" --console-address ":10000" /tmp/minio1/{1...4}/disk{1...4} /tmp/minio1/{5...8}/disk{1...4} >/tmp/minio1_1.log 2>&1 &
minio server --certs-dir /tmp/certs --address ":9002" --console-address ":11000" /tmp/minio2/{1...4}/disk{1...4} /tmp/minio2/{5...8}/disk{1...4} >/tmp/minio2_1.log 2>&1 &
echo "done"

if [ ! -f ./mc ]; then
	echo -n "Downloading MinIO client ..."

### 1.2 Host Multiple Tenants on Multiple Drives (Erasure Code)

Use the following commands to host 3 tenants on multiple drives:

```sh
minio server --address :9001 /disk{1...4}/data/tenant1
minio server --address :9002 /disk{1...4}/data/tenant2
minio server --address :9003 /disk{1...4}/data/tenant3
```

![Example-2](https://github.com/minio/minio/blob/master/docs/screenshots/Example-2.jpg?raw=true)

## 2. Distributed Deployment

# Compression Guide [![Slack](https://slack.min.io/slack?type=svg)](https://slack.min.io)

MinIO server allows streaming compression to ensure efficient disk space usage.
Compression happens inflight, i.e objects are compressed before being written to disk(s).
MinIO uses [`klauspost/compress/s2`](https://github.com/klauspost/compress/tree/master/s2)
streaming compression due to its stability and performance.

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package disk_test

import (
	"testing"

	"github.com/minio/minio/internal/disk"
)

func TestFree(t *testing.T) {
	di, err := disk.GetInfo(t.TempDir(), true)
	if err != nil {
		t.Fatal(err)
	}

	if di.FSType == "UNKNOWN" {
		t.Error("Unexpected FSType", di.FSType)
	}