# 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.

}

// Similar to 'len(slice)' but returns the actual elements count
// skipping the unallocated elements.
func diskCount(disks []StorageAPI) int {
	diskCount := 0
	for _, disk := range disks {
		if disk == nil {
			continue
		}
		diskCount++
	}
	return diskCount
}

// hashOrder - hashes input key to return consistent
// hashed integer slice. Returned integer order is salted

	Exists  bool      `msg:"ex"`           // Returns whether the file existed on disk.
	Error   string    `msg:"er,omitempty"` // Returns any error when reading.
	Data    []byte    `msg:"d"`            // Contains all data of file.
	Modtime time.Time `msg:"m"`            // Modtime of file on disk.
}

// DeleteVersionHandlerParams are parameters for DeleteVersionHandler

	healSeqMap map[string]*healSequence // Indexed by endpoint
	// keep track of the healing status of disks in the memory
	//   false: the disk needs to be healed but no healing routine is started
	//    true: the disk is currently healing
	healLocalDisks map[Endpoint]bool
	healStatus     map[string]healingTracker // Indexed by disk ID
}

// newHealState - initialize global heal state management

# 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

	"${PWD}/mc" mb --with-versioning minio/bucket

	for i in $(seq 1 4); do
		"${PWD}/mc" cp /etc/hosts minio/bucket/testobj

		sudo chown -R root. "${WORK_DIR}/disk${i}"

		"${PWD}/mc" cp /etc/hosts minio/bucket/testobj

		sudo chown -R ${USER}. "${WORK_DIR}/disk${i}"
	done

	for vid in $("${PWD}/mc" ls --json --versions minio/bucket/testobj | jq -r .versionId); do
		"${PWD}/mc" cat --vid "${vid}" minio/bucket/testobj | md5sum

	// Collect any disk healing.
	healing, _ := getAggregatedBackgroundHealState(ctx, nil)
	healDisks := make(map[string]struct{}, len(healing.HealDisks))
	for _, disk := range healing.HealDisks {
		healDisks[disk] = struct{}{}
	}

	// find all disks which belong to each respective endpoints
	for i, disk := range storageInfo.Disks {
		if _, ok := healDisks[disk.Endpoint]; ok {

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 ..."

}

// currentPathUpdater provides a lightweight update function for keeping track of
// current objects for each disk.
// Returns a function that can be used to update the current object
// and a function to call to when processing finished.
func (p *scannerMetrics) currentPathUpdater(disk, initial string) (update func(path string), done func()) {
	initialPtr := unsafe.Pointer(&initial)
	tracker := &currentPathTracker{

		}
		totalCap += disk.TotalSpace
		totalFree += disk.AvailableSpace

		diskStats[disk.PoolIndex].AvailableSpace += disk.AvailableSpace
		diskStats[disk.PoolIndex].TotalSpace += disk.TotalSpace
	}
	r.PercentFreeGoal = float64(totalFree) / float64(totalCap)

	now := time.Now()
	for idx := range z.serverPools {
		r.PoolStats[idx] = &rebalanceStats{
			Buckets:           make([]string, len(buckets)),