Bootstrap Parameters

Bootstrap Parameters

The introduction of bootstrap parameters in KubeVela controller are listed as below

Parameter Name	Type	Default Value	Description
use-webhook	bool	false	Use Admission Webhook
webhook-cert-dir	string	/k8s-webhook-server/serving-certs	The directory of Admission Webhook cert/secret
webhook-port	int	9443	The address of Admission Webhook
metrics-addr	string	:8080	The address of Prometheus metrics
enable-leader-election	bool	false	Enable Leader Election for Controller Manager and ensure that only one replica is active
leader-election-namespace	string	“”	The namespace of Leader Election ConfigMap
log-file-path	string	“”	The log file path
log-file-max-size	int	1024	The maximum size (MBi) of log files
log-debug	bool	false	Set the logging level to DEBUG, used in develop environment
application-revision-limit	int	2	The maximum number of application revisions to keep. When the number of revisions exceeeds this number, older version will be discarded
definition-revision-limit	int	2	The maximum number of definition revisions to keep
autogen-workload-definition	bool	true	Generate WorkloadDefinition for ComponentDefinition automatically
health-addr	string	:9440	The address of health check
disable-caps	string	“”	Disable internal capabilities
storage-driver	string	Local	The storage driver for applications
application-re-sync-period	time	5m	Re-sync period for application to re-sync, also known as the state-keep interval.
informer-sync-period	time	10h	The re-sync period for informer in controller-runtime. This is a system-level configuration.
reconcile-timeout	time	3m	The timeout for controller reconcile.
system-definition-namespace	string	vela-system	The namespace for storing system definitions
concurrent-reconciles	int	4	The number of threads that controller uses to process requests
kube-api-qps	int	50	The QPS for controller to access apiserver
kube-api-burst	int	100	The burst for controller to access apiserver
oam-spec-var	string	v0.3	The version of OAM spec to use
pprof-addr	string	“”	The address of pprof, default to be emtpy to disable pprof
perf-enabled	bool	false	Enable performance logging, working with monitoring tools like Loki and Grafana to discover performance bottleneck
enable-cluster-gateway	bool	false	Enable multi cluster feature
max-workflow-wait-backoff-time	int	60	the maximal backoff interval for workflow to retry when workflow step is waiting (unit: second)
max-workflow-failed-backoff-time	int	300	the maximal backoff interval for workflow to retry when workflow step fails (unit: second)
max-workflow-step-error-retry-times	int	10	the maximal retry times for workflow to retry when workflow step fails
reconcile-timeout	time	3m	the timeout for controller reconcile
reconcile-termination-graceful-period	time	5s	graceful period for terminating reconcile

Other parameters not listed in the table are old parameters used in previous versions, the latest version ( v1.1 ) does not use them.

application-re-sync-period: The resync time of applications when no changes were made. A short time may cause controller to reconcile frequently but uselessly. The regular reconciles of applications can help ensure that application and its components keep up-to-date in case some unexpected differences.
concurrent-reconciles: The number of threads to use for controller to handle requests. When rich CPU resources are available, a small number of working threads may lead to insufficient usage of CPU resources.
kube-api-qps / kube-api-burst: The rate limit for KubeVela controller to access apiserver. When managed applications are complex (containing multiple components and resources), if the access rate of apiserver is limited, it will be hard to increase the concurrency of KubeVela controller. However, high access rate may cause huge burden to apiserver. It is critical to keep a balance when handling massive applications.
pprof-addr: The pprof address to enable controller performance debugging.
perf-enabled: Use this flag if you would like to check time costs for different stages when reconciling applications. Switch it off to simplify loggings.

Several sets of recommended parameter configurations are enclosed in section Performance Fine-tuning.

You can use --feature-gates=XXX=true to enable feature XXX. There are a list of feature gates allow you to enable advanced features or alpha features.

AuthenticateApplication: enable the authentication for application.
ZstdResourceTracker: enables the zstd compression for ResourceTracker. It can be useful if you have large application that needs to dispatch lots of resources or large resources (like CRD or huge ConfigMap), which at the cost of slower processing speed due to the extra overhead for compression and decompression. Default to true.
ZstdApplicationRevision: enables the zstd compression for ApplicationRevision. Similar to ZstdResourceTracker, this can help save the storage space greatly. Default to true.
ApplyOnce: enable the apply-once feature for all applications. If enabled, no StateKeep will be run, ResourceTracker will also disable the storage of all resource data, only metadata will be kept.
MultiStageComponentApply: enable multi-stage feature for component. If enabled, the dispatch of manifests is performed in batches according to the stage.
ApplyResourceByUpdate: enforces the modification of resource through update requests. If not set, the resource modification will use patch requests (three-way-strategy-merge-patch). The side effect of enabling this feature is that the request traffic will increase due to the increase of bytes transferred and the more frequent resource mutation failure due to the potential conflicts. If set, KubeVela controller will enforce strong restriction on the managed resource that external system would be unable to make modifications to the KubeVela managed resource. In other words, no merge for modifications from multiple sources. Only KubeVela keeps the Source-of-Truth for the resource.
PreDispatchDryRun: enable dryrun before dispatching resources. Enable this flag can help prevent unsuccessful dispatch resources entering resourcetracker and improve the user experiences of gc but at the cost of increasing network requests. This flag is set to true by default.

Last updated on Aug 4, 2023 by Daniel Higuero