else if (a.cas(v = a.value, fn(v, x))) break;
        else if (n >= NCPU || cells != as) collide = false; // At max size or stale
        else if (!collide) collide = true;
        else if (busy == 0 && casBusy()) {
          try {
            if (cells == as) { // Expand table unless stale
              Cell[] rs = new Cell[n << 1];
              for (int i = 0; i < n; ++i) rs[i] = as[i];
              cells = rs;

 * [okhttp-signpost](https://github.com/pakerfeldt/okhttp-signpost): OAuth signing with signpost and OkHttp.
 * [okhttp-staleiferror-interceptor](https://github.com/PeelTechnologies/okhttp-staleiferror-interceptor/): serve stale responses when the server isn’t reachable.
 * [okhttp-stats](https://github.com/flipkart-incubator/okhttp-stats): Get stats like average network speed.

		return errFileNotFound
	}
	if cache.status == scanStateSuccess || cache.status == scanStateStarted {
		if time.Since(cache.lastUpdate) > metacacheMaxRunningAge {
			// We got a stale entry, mark error on handling server.
			err := fmt.Errorf("timeout: list %s not updated", cache.id)
			cache.error = err.Error()
			cache.status = scanStateError
			rpc.UpdateMetacacheListing(ctx, cache)
			return err

	sys.Lock()
	for _, bucket := range buckets {
		delete(sys.metadataMap, bucket)
		globalBucketMonitor.DeleteBucket(bucket)
	}
	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 {

* Correctness at startup; with the sequencing above, items are only processed once all informers are synced. This means queries will not return stale data at startup.
* Deduping of identical events
* Automatic retrying of failed events (configurable)

The above logic is critical to handle correctly to ensure correctness of a controller.

	// GlobalStaleUploadsExpiry - Expiry duration after which the uploads in multipart,
	// tmp directory are deemed stale.
	GlobalStaleUploadsExpiry = time.Hour * 24 // 24 hrs.

	// GlobalStaleUploadsCleanupInterval - Cleanup interval when the stale uploads cleanup is initiated.
	GlobalStaleUploadsCleanupInterval = time.Hour * 6 // 6 hrs.

	// Refresh interval to update in-memory iam config cache.

  private fun getCacheOnlyResponse(request: Request): Response? {
    if (client.cache != null) {
      try {
        // Use the cache without hitting the network first
        // 504 code indicates that the Cache is stale
        val onlyIfCached =
          CacheControl.Builder()
            .onlyIfCached()
            .build()

        var cacheUrl = request.url

        val cacheRequest =

  // TODO GET preferred order - with tests to confirm this
  // 1. successful fresh cached GET response
  // 2. unsuccessful (404, 500) fresh cached GET response
  // 3. successful network response
  // 4. successful stale cached GET response
  // 5. unsuccessful response
  @Test
  fun usesCache() {
    val cache = Cache(cacheFs, "cache".toPath(), (100 * 1024).toLong())

	var err error

	log.Debugf("Checking pod: %s in ns: %s is enabled for ambient", addCmd.PodName, addCmd.PodNamespace)
	// The plugin already consulted the k8s API - but on this end handler caches may be stale, so retry a few times if we get no pod.
	for ambientPod, err = s.handlers.GetPodIfAmbient(addCmd.PodName, addCmd.PodNamespace); (ambientPod == nil) && (retries < maxStaleRetries); retries++ {
		if err != nil {
			return err

		// value is cached we should attempt to invalidate it if such calls
		// were attempted. This can lead to false success under certain conditions
		// - this change attempts to avoid stale information if the underlying
		// transport is already down.
		return "", errDiskNotFound
	}

	// This call should never be over the network, this is always
	// a cached value - caller should make sure to use this