feat: make eventProcessingInterval option configurable (default is 0.1s)

Signed-off-by: Mykola Pelekh <mpelekh@demonware.net>

controller/cache/cache.go

@@ -72,6 +72,9 @@ const (
 	// EnvClusterCacheBatchEventsProcessing is the env variable to control whether to enable batch events processing
 	EnvClusterCacheBatchEventsProcessing = "ARGOCD_CLUSTER_CACHE_BATCH_EVENTS_PROCESSING"
 
+	// EnvClusterCacheEventProcessingInterval is the env variable to control the interval between processing events when BatchEventsProcessing is enabled
+	EnvClusterCacheEventProcessingInterval = "ARGOCD_CLUSTER_CACHE_EVENT_PROCESSING_INTERVAL"
+
 	// AnnotationIgnoreResourceUpdates when set to true on an untracked resource,
 	// argo will apply `ignoreResourceUpdates` configuration on it.
 	AnnotationIgnoreResourceUpdates = "argocd.argoproj.io/ignore-resource-updates"
@@ -109,6 +112,9 @@ var (
 
 	// clusterCacheBatchEventsProcessing specifies whether to enable batch events processing
 	clusterCacheBatchEventsProcessing bool = false
+
+	// clusterCacheEventProcessingInterval specifies the interval between processing events when BatchEventsProcessing is enabled
+	clusterCacheEventProcessingInterval = 100 * time.Millisecond
 )
 
 func init() {
@@ -121,6 +127,7 @@ func init() {
 	clusterCacheAttemptLimit = int32(env.ParseNumFromEnv(EnvClusterCacheAttemptLimit, int(clusterCacheAttemptLimit), 1, math.MaxInt32))
 	clusterCacheRetryUseBackoff = env.ParseBoolFromEnv(EnvClusterCacheRetryUseBackoff, false)
 	clusterCacheBatchEventsProcessing = env.ParseBoolFromEnv(EnvClusterCacheBatchEventsProcessing, false)
+	clusterCacheEventProcessingInterval = env.ParseDurationFromEnv(EnvClusterCacheEventProcessingInterval, clusterCacheEventProcessingInterval, 0, math.MaxInt64)
 }
 
 type LiveStateCache interface {
@@ -562,6 +569,7 @@ func (c *liveStateCache) getCluster(server string) (clustercache.ClusterCache, e
 		clustercache.SetRetryOptions(clusterCacheAttemptLimit, clusterCacheRetryUseBackoff, isRetryableError),
 		clustercache.SetRespectRBAC(respectRBAC),
 		clustercache.SetBatchEventsProcessing(clusterCacheBatchEventsProcessing),
+		clustercache.SetEventProcessingInterval(clusterCacheEventProcessingInterval),
 	}
 
 	clusterCache = clustercache.NewClusterCache(clusterCacheConfig, clusterCacheOpts...)

docs/operator-manual/high_availability.md

@@ -135,6 +135,10 @@ stringData:
   and the controller is overwhelmed by the number of events. The default value is `false`, which means that the controller
   processes events one by one.
 
+* `ARGOCD_CLUSTER_CACHE_BATCH_EVENTS_PROCESSING_INTERVAL` - environment variable controlling the interval for processing events in a batch.
+  The valid value is in the format of Go time duration string, e.g. `1ms`, `1s`, `1m`, `1h`. The default value is `100ms`.
+  The variable is used only when `ARGOCD_CLUSTER_CACHE_BATCH_EVENTS_PROCESSING` is set to `true`.
+
 * `ARGOCD_APPLICATION_TREE_SHARD_SIZE` - environment variable controlling the max number of resources stored in one Redis
   key. Splitting application tree into multiple keys helps to reduce the amount of traffic between the controller and Redis.
   The default value is 0, which means that the application tree is stored in a single Redis key. The reasonable value is 100.