Update custom-metrics-apiserver and metrics-server

This commit is contained in:
Johannes Würbach 2020-09-27 22:14:53 +02:00
parent 4c673534f2
commit b480e45a67
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915 changed files with 63694 additions and 106514 deletions

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@ -21,11 +21,11 @@ import (
"sync"
"time"
"k8s.io/apimachinery/pkg/api/meta"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/apimachinery/pkg/util/clock"
utilruntime "k8s.io/apimachinery/pkg/util/runtime"
"k8s.io/apimachinery/pkg/util/wait"
"k8s.io/client-go/util/retry"
"k8s.io/utils/buffer"
"k8s.io/klog"
@ -46,15 +46,6 @@ import (
// An object state is either "absent" or present with a
// ResourceVersion and other appropriate content.
//
// A SharedInformer gets object states from apiservers using a
// sequence of LIST and WATCH operations. Through this sequence the
// apiservers provide a sequence of "collection states" to the
// informer, where each collection state defines the state of every
// object of the collection. No promise --- beyond what is implied by
// other remarks here --- is made about how one informer's sequence of
// collection states relates to a different informer's sequence of
// collection states.
//
// A SharedInformer maintains a local cache, exposed by GetStore() and
// by GetIndexer() in the case of an indexed informer, of the state of
// each relevant object. This cache is eventually consistent with the
@ -67,10 +58,17 @@ import (
// To be formally complete, we say that the absent state meets any
// restriction by label selector or field selector.
//
// For a given informer and relevant object ID X, the sequence of
// states that appears in the informer's cache is a subsequence of the
// states authoritatively associated with X. That is, some states
// might never appear in the cache but ordering among the appearing
// states is correct. Note, however, that there is no promise about
// ordering between states seen for different objects.
//
// The local cache starts out empty, and gets populated and updated
// during `Run()`.
//
// As a simple example, if a collection of objects is henceforeth
// As a simple example, if a collection of objects is henceforth
// unchanging, a SharedInformer is created that links to that
// collection, and that SharedInformer is `Run()` then that
// SharedInformer's cache eventually holds an exact copy of that
@ -91,6 +89,10 @@ import (
// a given object, and `SplitMetaNamespaceKey(key)` to split a key
// into its constituent parts.
//
// Every query against the local cache is answered entirely from one
// snapshot of the cache's state. Thus, the result of a `List` call
// will not contain two entries with the same namespace and name.
//
// A client is identified here by a ResourceEventHandler. For every
// update to the SharedInformer's local cache and for every client
// added before `Run()`, eventually either the SharedInformer is
@ -106,7 +108,16 @@ import (
// and index updates happen before such a prescribed notification.
// For a given SharedInformer and client, the notifications are
// delivered sequentially. For a given SharedInformer, client, and
// object ID, the notifications are delivered in order.
// object ID, the notifications are delivered in order. Because
// `ObjectMeta.UID` has no role in identifying objects, it is possible
// that when (1) object O1 with ID (e.g. namespace and name) X and
// `ObjectMeta.UID` U1 in the SharedInformer's local cache is deleted
// and later (2) another object O2 with ID X and ObjectMeta.UID U2 is
// created the informer's clients are not notified of (1) and (2) but
// rather are notified only of an update from O1 to O2. Clients that
// need to detect such cases might do so by comparing the `ObjectMeta.UID`
// field of the old and the new object in the code that handles update
// notifications (i.e. `OnUpdate` method of ResourceEventHandler).
//
// A client must process each notification promptly; a SharedInformer
// is not engineered to deal well with a large backlog of
@ -114,11 +125,6 @@ import (
// to something else, for example through a
// `client-go/util/workqueue`.
//
// Each query to an informer's local cache --- whether a single-object
// lookup, a list operation, or a use of one of its indices --- is
// answered entirely from one of the collection states received by
// that informer.
//
// A delete notification exposes the last locally known non-absent
// state, except that its ResourceVersion is replaced with a
// ResourceVersion in which the object is actually absent.
@ -128,14 +134,23 @@ type SharedInformer interface {
// between different handlers.
AddEventHandler(handler ResourceEventHandler)
// AddEventHandlerWithResyncPeriod adds an event handler to the
// shared informer using the specified resync period. The resync
// operation consists of delivering to the handler a create
// notification for every object in the informer's local cache; it
// does not add any interactions with the authoritative storage.
// shared informer with the requested resync period; zero means
// this handler does not care about resyncs. The resync operation
// consists of delivering to the handler an update notification
// for every object in the informer's local cache; it does not add
// any interactions with the authoritative storage. Some
// informers do no resyncs at all, not even for handlers added
// with a non-zero resyncPeriod. For an informer that does
// resyncs, and for each handler that requests resyncs, that
// informer develops a nominal resync period that is no shorter
// than the requested period but may be longer. The actual time
// between any two resyncs may be longer than the nominal period
// because the implementation takes time to do work and there may
// be competing load and scheduling noise.
AddEventHandlerWithResyncPeriod(handler ResourceEventHandler, resyncPeriod time.Duration)
// GetStore returns the informer's local cache as a Store.
GetStore() Store
// GetController gives back a synthetic interface that "votes" to start the informer
// GetController is deprecated, it does nothing useful
GetController() Controller
// Run starts and runs the shared informer, returning after it stops.
// The informer will be stopped when stopCh is closed.
@ -159,21 +174,32 @@ type SharedIndexInformer interface {
}
// NewSharedInformer creates a new instance for the listwatcher.
func NewSharedInformer(lw ListerWatcher, objType runtime.Object, resyncPeriod time.Duration) SharedInformer {
return NewSharedIndexInformer(lw, objType, resyncPeriod, Indexers{})
func NewSharedInformer(lw ListerWatcher, exampleObject runtime.Object, defaultEventHandlerResyncPeriod time.Duration) SharedInformer {
return NewSharedIndexInformer(lw, exampleObject, defaultEventHandlerResyncPeriod, Indexers{})
}
// NewSharedIndexInformer creates a new instance for the listwatcher.
func NewSharedIndexInformer(lw ListerWatcher, objType runtime.Object, defaultEventHandlerResyncPeriod time.Duration, indexers Indexers) SharedIndexInformer {
// The created informer will not do resyncs if the given
// defaultEventHandlerResyncPeriod is zero. Otherwise: for each
// handler that with a non-zero requested resync period, whether added
// before or after the informer starts, the nominal resync period is
// the requested resync period rounded up to a multiple of the
// informer's resync checking period. Such an informer's resync
// checking period is established when the informer starts running,
// and is the maximum of (a) the minimum of the resync periods
// requested before the informer starts and the
// defaultEventHandlerResyncPeriod given here and (b) the constant
// `minimumResyncPeriod` defined in this file.
func NewSharedIndexInformer(lw ListerWatcher, exampleObject runtime.Object, defaultEventHandlerResyncPeriod time.Duration, indexers Indexers) SharedIndexInformer {
realClock := &clock.RealClock{}
sharedIndexInformer := &sharedIndexInformer{
processor: &sharedProcessor{clock: realClock},
indexer: NewIndexer(DeletionHandlingMetaNamespaceKeyFunc, indexers),
listerWatcher: lw,
objectType: objType,
objectType: exampleObject,
resyncCheckPeriod: defaultEventHandlerResyncPeriod,
defaultEventHandlerResyncPeriod: defaultEventHandlerResyncPeriod,
cacheMutationDetector: NewCacheMutationDetector(fmt.Sprintf("%T", objType)),
cacheMutationDetector: NewCacheMutationDetector(fmt.Sprintf("%T", exampleObject)),
clock: realClock,
}
return sharedIndexInformer
@ -228,6 +254,19 @@ func WaitForCacheSync(stopCh <-chan struct{}, cacheSyncs ...InformerSynced) bool
return true
}
// `*sharedIndexInformer` implements SharedIndexInformer and has three
// main components. One is an indexed local cache, `indexer Indexer`.
// The second main component is a Controller that pulls
// objects/notifications using the ListerWatcher and pushes them into
// a DeltaFIFO --- whose knownObjects is the informer's local cache
// --- while concurrently Popping Deltas values from that fifo and
// processing them with `sharedIndexInformer::HandleDeltas`. Each
// invocation of HandleDeltas, which is done with the fifo's lock
// held, processes each Delta in turn. For each Delta this both
// updates the local cache and stuffs the relevant notification into
// the sharedProcessor. The third main component is that
// sharedProcessor, which is responsible for relaying those
// notifications to each of the informer's clients.
type sharedIndexInformer struct {
indexer Indexer
controller Controller
@ -235,9 +274,13 @@ type sharedIndexInformer struct {
processor *sharedProcessor
cacheMutationDetector MutationDetector
// This block is tracked to handle late initialization of the controller
listerWatcher ListerWatcher
objectType runtime.Object
// objectType is an example object of the type this informer is
// expected to handle. Only the type needs to be right, except
// that when that is `unstructured.Unstructured` the object's
// `"apiVersion"` and `"kind"` must also be right.
objectType runtime.Object
// resyncCheckPeriod is how often we want the reflector's resync timer to fire so it can call
// shouldResync to check if any of our listeners need a resync.
@ -293,7 +336,10 @@ type deleteNotification struct {
func (s *sharedIndexInformer) Run(stopCh <-chan struct{}) {
defer utilruntime.HandleCrash()
fifo := NewDeltaFIFO(MetaNamespaceKeyFunc, s.indexer)
fifo := NewDeltaFIFOWithOptions(DeltaFIFOOptions{
KnownObjects: s.indexer,
EmitDeltaTypeReplaced: true,
})
cfg := &Config{
Queue: fifo,
@ -452,19 +498,33 @@ func (s *sharedIndexInformer) HandleDeltas(obj interface{}) error {
// from oldest to newest
for _, d := range obj.(Deltas) {
switch d.Type {
case Sync, Added, Updated:
isSync := d.Type == Sync
case Sync, Replaced, Added, Updated:
s.cacheMutationDetector.AddObject(d.Object)
if old, exists, err := s.indexer.Get(d.Object); err == nil && exists {
if err := s.indexer.Update(d.Object); err != nil {
return err
}
isSync := false
switch {
case d.Type == Sync:
// Sync events are only propagated to listeners that requested resync
isSync = true
case d.Type == Replaced:
if accessor, err := meta.Accessor(d.Object); err == nil {
if oldAccessor, err := meta.Accessor(old); err == nil {
// Replaced events that didn't change resourceVersion are treated as resync events
// and only propagated to listeners that requested resync
isSync = accessor.GetResourceVersion() == oldAccessor.GetResourceVersion()
}
}
}
s.processor.distribute(updateNotification{oldObj: old, newObj: d.Object}, isSync)
} else {
if err := s.indexer.Add(d.Object); err != nil {
return err
}
s.processor.distribute(addNotification{newObj: d.Object}, isSync)
s.processor.distribute(addNotification{newObj: d.Object}, false)
}
case Deleted:
if err := s.indexer.Delete(d.Object); err != nil {
@ -476,6 +536,12 @@ func (s *sharedIndexInformer) HandleDeltas(obj interface{}) error {
return nil
}
// sharedProcessor has a collection of processorListener and can
// distribute a notification object to its listeners. There are two
// kinds of distribute operations. The sync distributions go to a
// subset of the listeners that (a) is recomputed in the occasional
// calls to shouldResync and (b) every listener is initially put in.
// The non-sync distributions go to every listener.
type sharedProcessor struct {
listenersStarted bool
listenersLock sync.RWMutex
@ -567,6 +633,17 @@ func (p *sharedProcessor) resyncCheckPeriodChanged(resyncCheckPeriod time.Durati
}
}
// processorListener relays notifications from a sharedProcessor to
// one ResourceEventHandler --- using two goroutines, two unbuffered
// channels, and an unbounded ring buffer. The `add(notification)`
// function sends the given notification to `addCh`. One goroutine
// runs `pop()`, which pumps notifications from `addCh` to `nextCh`
// using storage in the ring buffer while `nextCh` is not keeping up.
// Another goroutine runs `run()`, which receives notifications from
// `nextCh` and synchronously invokes the appropriate handler method.
//
// processorListener also keeps track of the adjusted requested resync
// period of the listener.
type processorListener struct {
nextCh chan interface{}
addCh chan interface{}
@ -580,11 +657,22 @@ type processorListener struct {
// we should try to do something better.
pendingNotifications buffer.RingGrowing
// requestedResyncPeriod is how frequently the listener wants a full resync from the shared informer
// requestedResyncPeriod is how frequently the listener wants a
// full resync from the shared informer, but modified by two
// adjustments. One is imposing a lower bound,
// `minimumResyncPeriod`. The other is another lower bound, the
// sharedProcessor's `resyncCheckPeriod`, that is imposed (a) only
// in AddEventHandlerWithResyncPeriod invocations made after the
// sharedProcessor starts and (b) only if the informer does
// resyncs at all.
requestedResyncPeriod time.Duration
// resyncPeriod is how frequently the listener wants a full resync from the shared informer. This
// value may differ from requestedResyncPeriod if the shared informer adjusts it to align with the
// informer's overall resync check period.
// resyncPeriod is the threshold that will be used in the logic
// for this listener. This value differs from
// requestedResyncPeriod only when the sharedIndexInformer does
// not do resyncs, in which case the value here is zero. The
// actual time between resyncs depends on when the
// sharedProcessor's `shouldResync` function is invoked and when
// the sharedIndexInformer processes `Sync` type Delta objects.
resyncPeriod time.Duration
// nextResync is the earliest time the listener should get a full resync
nextResync time.Time
@ -648,29 +736,21 @@ func (p *processorListener) run() {
// delivering again.
stopCh := make(chan struct{})
wait.Until(func() {
// this gives us a few quick retries before a long pause and then a few more quick retries
err := wait.ExponentialBackoff(retry.DefaultRetry, func() (bool, error) {
for next := range p.nextCh {
switch notification := next.(type) {
case updateNotification:
p.handler.OnUpdate(notification.oldObj, notification.newObj)
case addNotification:
p.handler.OnAdd(notification.newObj)
case deleteNotification:
p.handler.OnDelete(notification.oldObj)
default:
utilruntime.HandleError(fmt.Errorf("unrecognized notification: %T", next))
}
for next := range p.nextCh {
switch notification := next.(type) {
case updateNotification:
p.handler.OnUpdate(notification.oldObj, notification.newObj)
case addNotification:
p.handler.OnAdd(notification.newObj)
case deleteNotification:
p.handler.OnDelete(notification.oldObj)
default:
utilruntime.HandleError(fmt.Errorf("unrecognized notification: %T", next))
}
// the only way to get here is if the p.nextCh is empty and closed
return true, nil
})
// the only way to get here is if the p.nextCh is empty and closed
if err == nil {
close(stopCh)
}
}, 1*time.Minute, stopCh)
// the only way to get here is if the p.nextCh is empty and closed
close(stopCh)
}, 1*time.Second, stopCh)
}
// shouldResync deterimines if the listener needs a resync. If the listener's resyncPeriod is 0,