kubernetes/staging/src/k8s.io/apiserver/pkg/storage/etcd3/compact.go

const compactRevKey …

var endpointsMapMu …

var endpointsMap …

func init() { … }

// StartCompactor starts a compactor in the background to compact old version of keys that's not needed.
// By default, we save the most recent 5 minutes data and compact versions > 5minutes ago.
// It should be enough for slow watchers and to tolerate burst.
// TODO: We might keep a longer history (12h) in the future once storage API can take advantage of past version of keys.
func StartCompactor(ctx context.Context, client *clientv3.Client, compactInterval time.Duration) { … }

// compactor periodically compacts historical versions of keys in etcd.
// It will compact keys with versions older than given interval.
// In other words, after compaction, it will only contain keys set during last interval.
// Any API call for the older versions of keys will return error.
// Interval is the time interval between each compaction. The first compaction happens after "interval".
func compactor(ctx context.Context, client *clientv3.Client, interval time.Duration) { … }

// compact compacts etcd store and returns current rev.
// It will return the current compact time and global revision if no error occurred.
// Note that CAS fail will not incur any error.
func compact(ctx context.Context, client *clientv3.Client, t, rev int64) (int64, int64, error) { … }