outlierdetection

Documentation

Overview

Package outlierdetection provides an implementation of the outlier detection LB policy, as defined in https://github.com/grpc/proposal/blob/master/A50-xds-outlier-detection.md.

Index

• Constants
• type FailurePercentageEjection
  • func (fpe *FailurePercentageEjection) Equal(fpe2 *FailurePercentageEjection) bool
• type LBConfig
  • func (lbc *LBConfig) EqualIgnoringChildPolicy(lbc2 *LBConfig) bool
• type SuccessRateEjection
  • func (sre *SuccessRateEjection) Equal(sre2 *SuccessRateEjection) bool

Constants

const Name = "outlier_detection_experimental"

Name is the name of the outlier detection balancer.

Types

type FailurePercentageEjection

type FailurePercentageEjection struct {
	// Threshold is the failure percentage to use when determining failure
	// percentage-based outlier detection. If the failure percentage of a given
	// host is greater than or equal to this value, it will be ejected. Defaults
	// to 85.
	Threshold uint32 `json:"threshold,omitempty"`
	// EnforcementPercentage is the % chance that a host will be actually
	// ejected when an outlier status is detected through failure percentage
	// statistics. This setting can be used to disable ejection or to ramp it up
	// slowly. Defaults to 0.
	EnforcementPercentage uint32 `json:"enforcementPercentage,omitempty"`
	// MinimumHosts is the minimum number of hosts in a cluster in order to
	// perform failure percentage-based ejection. If the total number of hosts
	// in the cluster is less than this value, failure percentage-based ejection
	// will not be performed. Defaults to 5.
	MinimumHosts uint32 `json:"minimumHosts,omitempty"`
	// RequestVolume is the minimum number of total requests that must be
	// collected in one interval (as defined by the interval duration above) to
	// perform failure percentage-based ejection for this host. If the volume is
	// lower than this setting, failure percentage-based ejection will not be
	// performed for this host. Defaults to 50.
	RequestVolume uint32 `json:"requestVolume,omitempty"`
}

FailurePercentageEjection is parameters for the failure percentage algorithm. This algorithm ejects individual endpoints whose failure rate is greater than some threshold, independently of any other endpoint.

func (*FailurePercentageEjection) Equal

func (fpe *FailurePercentageEjection) Equal(fpe2 *FailurePercentageEjection) bool

Equal returns whether the FailurePercentageEjection is the same with the parameter.

type LBConfig

type LBConfig struct {
	serviceconfig.LoadBalancingConfig `json:"-"`
	// Interval is the time interval between ejection analysis sweeps. This can
	// result in both new ejections as well as addresses being returned to
	// service. Defaults to 10s.
	Interval time.Duration `json:"interval,omitempty"`
	// BaseEjectionTime is the base time that a host is ejected for. The real
	// time is equal to the base time multiplied by the number of times the host
	// has been ejected and is capped by MaxEjectionTime. Defaults to 30s.
	BaseEjectionTime time.Duration `json:"baseEjectionTime,omitempty"`
	// MaxEjectionTime is the maximum time that an address is ejected for. If
	// not specified, the default value (300s) or the BaseEjectionTime value is
	// applied, whichever is larger.
	MaxEjectionTime time.Duration `json:"maxEjectionTime,omitempty"`
	// MaxEjectionPercent is the maximum % of an upstream cluster that can be
	// ejected due to outlier detection. Defaults to 10% but will eject at least
	// one host regardless of the value.
	MaxEjectionPercent uint32 `json:"maxEjectionPercent,omitempty"`
	// SuccessRateEjection is the parameters for the success rate ejection
	// algorithm. If set, success rate ejections will be performed.
	SuccessRateEjection *SuccessRateEjection `json:"successRateEjection,omitempty"`
	// FailurePercentageEjection is the parameters for the failure percentage
	// algorithm. If set, failure rate ejections will be performed.
	FailurePercentageEjection *FailurePercentageEjection `json:"failurePercentageEjection,omitempty"`
	// ChildPolicy is the config for the child policy.
	ChildPolicy *internalserviceconfig.BalancerConfig `json:"childPolicy,omitempty"`
}

LBConfig is the config for the outlier detection balancer.

func (*LBConfig) EqualIgnoringChildPolicy

func (lbc *LBConfig) EqualIgnoringChildPolicy(lbc2 *LBConfig) bool

EqualIgnoringChildPolicy returns whether the LBConfig is same with the parameter outside of the child policy, only comparing the Outlier Detection specific configuration.

type SuccessRateEjection

type SuccessRateEjection struct {
	// StddevFactor is used to determine the ejection threshold for
	// success rate outlier ejection. The ejection threshold is the difference
	// between the mean success rate, and the product of this factor and the
	// standard deviation of the mean success rate: mean - (stdev *
	// success_rate_stdev_factor). This factor is divided by a thousand to get a
	// double. That is, if the desired factor is 1.9, the runtime value should
	// be 1900. Defaults to 1900.
	StdevFactor uint32 `json:"stdevFactor,omitempty"`
	// EnforcementPercentage is the % chance that a host will be actually ejected
	// when an outlier status is detected through success rate statistics. This
	// setting can be used to disable ejection or to ramp it up slowly. Defaults
	// to 100.
	EnforcementPercentage uint32 `json:"enforcementPercentage,omitempty"`
	// MinimumHosts is the number of hosts in a cluster that must have enough
	// request volume to detect success rate outliers. If the number of hosts is
	// less than this setting, outlier detection via success rate statistics is
	// not performed for any host in the cluster. Defaults to 5.
	MinimumHosts uint32 `json:"minimumHosts,omitempty"`
	// RequestVolume is the minimum number of total requests that must be
	// collected in one interval (as defined by the interval duration above) to
	// include this host in success rate based outlier detection. If the volume
	// is lower than this setting, outlier detection via success rate statistics
	// is not performed for that host. Defaults to 100.
	RequestVolume uint32 `json:"requestVolume,omitempty"`
}

SuccessRateEjection is parameters for the success rate ejection algorithm. This algorithm monitors the request success rate for all endpoints and ejects individual endpoints whose success rates are statistical outliers.

func (*SuccessRateEjection) Equal

func (sre *SuccessRateEjection) Equal(sre2 *SuccessRateEjection) bool

Equal returns whether the SuccessRateEjection is the same with the parameter.