cache.iamUserGroupMemberships = newCache.iamUserGroupMemberships
		cache.iamUserPolicyMap = newCache.iamUserPolicyMap
		cache.iamUsersMap = newCache.iamUsersMap
		// For STS policy map, we need to merge the new cache with the existing
		// cache because the periodic IAM reload is partial. The periodic load
		// here is to account for STS policy mapping changes that should apply

			if err != errFileNotFound {
				return err
			}
		}
	}

	if len(xlMeta.versions) != 0 {
		// xl.meta must still exist for other versions, dataDir is purged.
		buf, err = xlMeta.AppendTo(metaDataPoolGet())
		defer metaDataPoolPut(buf)
		if err != nil {
			return err
		}

		return s.WriteAll(ctx, volume, pathJoin(path, xlStorageFormatFile), buf)
	}

| `minio_node_drive_reads_await`       | Average time for read requests to be served on a drive.  |
| `minio_node_drive_writes_per_sec`    | Writes per second on a drive.                            |
| `minio_node_drive_writes_kb_per_sec` | Kilobytes written per second on a drive.                 |
| `minio_node_drive_writes_await`      | Average time for write requests to be served on a drive. |

//	anonReq   - unsigned *http.Request to invoke the handler's response for anonymous requests.
//	policyFunc    - function to return bucketPolicy statement which would permit the anonymous request to be served.
//
// The test works in 2 steps, here is the description of the steps.
//
//	STEP 1: Call the handler with the unsigned HTTP request (anonReq), assert for the `ErrAccessDenied` error response.

		if err != nil {
			return wrapSRErr(err)
		}
		return nil
	}

	return nil
}

// PeerBucketMetadataUpdateHandler - merges the bucket metadata, save and ping other nodes
func (c *SiteReplicationSys) PeerBucketMetadataUpdateHandler(ctx context.Context, item madmin.SRBucketMeta) error {
	objectAPI := newObjectLayerFn()
	if objectAPI == nil {

			if dobj.VersionID == "" && rinfo.VersionPurgeStatus.Empty() {
				rinfo.ReplicationStatus = replication.Completed
				return
			}
		case isErrObjectNotFound(serr), isErrVersionNotFound(serr):
			// version being purged is already not found on target.
			if !rinfo.VersionPurgeStatus.Empty() {
				rinfo.VersionPurgeStatus = Complete
				return
			}
		case isErrReadQuorum(serr), isErrWriteQuorum(serr):

		}
		ContentLengthRange contentLengthRange
	}
}

// implemented to ensure that duplicate keys in JSON
// are merged together into a single JSON key, also
// to remove any extraneous JSON bodies.
//
// Go stdlib doesn't support parsing JSON with duplicate
// keys, so we need to use this technique to merge the
// keys.
func sanitizePolicy(r io.Reader) (io.Reader, error) {
	var buf bytes.Buffer
	e := json.NewEncoder(&buf)

	}
	for k, v := range d.Cache {
		clone.Cache[k] = v.clone()
	}
	return clone
}

// merge root of other into d.
// children of root will be flattened before being merged.
// Last update time will be set to the last updated.
func (d *dataUsageCache) merge(other dataUsageCache) {
	existingRoot := d.root()
	otherRoot := other.root()
	if existingRoot == nil && otherRoot == nil {
		return

var deletedSubSysKeys = map[string][]string{
	APISubSys: {apiReplicationWorkers, apiReplicationFailedWorkers},
	// Add future sub-system deleted keys
}

// Merge - merges a new config with all the
// missing values for default configs,
// returns a config.
func (c Config) Merge() Config {
	cp := New()
	for subSys, tgtKV := range c {
		for tgt := range tgtKV {
			ckvs := c[subSys][tgt]
			for _, kv := range cp[subSys][Default] {

		allDriveLabels...)
	driveReadsKBPerSecMD = NewGaugeMD(driveReadsKBPerSec,
		"Kilobytes read per second on a drive",
		allDriveLabels...)
	driveReadsAwaitMD = NewGaugeMD(driveReadsAwait,
		"Average time for read requests served on a drive",
		allDriveLabels...)
	driveWritesPerSecMD = NewGaugeMD(driveWritesPerSec,
		"Writes per second on a drive",
		allDriveLabels...)
	driveWritesKBPerSecMD = NewGaugeMD(driveWritesKBPerSec,