system

Documentation

Overview

Package system provides implementation of adaptive system protection.

Index

• Constants
• Variables
• func ClearRules() error
• func IsValidSystemRule(rule *Rule) error
• func LoadRules(rules []*Rule) (bool, error)
• type AdaptiveSlot
  • func (s *AdaptiveSlot) Check(ctx *base.EntryContext) *base.TokenResult
  • func (s *AdaptiveSlot) Order() uint32
• type AdaptiveStrategy
  • func (t AdaptiveStrategy) String() string
• type MetricType
  • func (t MetricType) String() string
• type Rule
  • func GetRules() []Rule
  • func (r *Rule) ResourceName() string
  • func (r *Rule) String() string
• type RuleMap

Constants

const (
	RuleCheckSlotOrder = 1000
)

Variables

var (
	DefaultAdaptiveSlot = &AdaptiveSlot{}
)

Functions

func ClearRules

func ClearRules() error

ClearRules clear all the previous rules

func IsValidSystemRule

func IsValidSystemRule(rule *Rule) error

IsValidSystemRule determine the system rule is valid or not

func LoadRules

func LoadRules(rules []*Rule) (bool, error)

LoadRules loads given system rules to the rule manager, while all previous rules will be replaced.

Types

type AdaptiveSlot

type AdaptiveSlot struct {
}

func (*AdaptiveSlot) Check

func (s *AdaptiveSlot) Check(ctx *base.EntryContext) *base.TokenResult

func (*AdaptiveSlot) Order

func (s *AdaptiveSlot) Order() uint32

type AdaptiveStrategy

type AdaptiveStrategy int32

const (
	NoAdaptive AdaptiveStrategy = -1
	// BBR represents the adaptive strategy based on ideas of TCP BBR.
	BBR AdaptiveStrategy = iota
)

func (AdaptiveStrategy) String

func (t AdaptiveStrategy) String() string

type MetricType

type MetricType uint32

const (
	// Load represents system load1 in Linux/Unix.
	Load MetricType = iota
	// AvgRT represents the average response time of all inbound requests.
	AvgRT
	// Concurrency represents the concurrency of all inbound requests.
	Concurrency
	// InboundQPS represents the QPS of all inbound requests.
	InboundQPS
	// CpuUsage represents the CPU usage percentage of the system.
	CpuUsage

	// MetricTypeSize indicates the enum size of MetricType.
	MetricTypeSize
)

func (MetricType) String

func (t MetricType) String() string

type Rule

type Rule struct {
	// ID represents the unique ID of the rule (optional).
	ID string `json:"id,omitempty"`
	// MetricType indicates the type of the trigger metric.
	MetricType MetricType `json:"metricType"`
	// TriggerCount represents the lower bound trigger of the adaptive strategy.
	// Adaptive strategies will not be activated until target metric has reached the trigger count.
	TriggerCount float64 `json:"triggerCount"`
	// Strategy represents the adaptive strategy.
	Strategy AdaptiveStrategy `json:"strategy"`
}

Rule describes the policy for system resiliency.

func GetRules

func GetRules() []Rule

GetRules returns all the rules based on copy. It doesn't take effect for system module if user changes the rule. GetRules need to compete system module's global lock and the high performance losses of copy,

reduce or do not call GetRules if possible

func (*Rule) ResourceName

func (r *Rule) ResourceName() string

func (*Rule) String

func (r *Rule) String() string

type RuleMap

type RuleMap map[MetricType][]*Rule