probabilisticsamplerprocessor

README

Probabilistic Sampling Processor

Supported pipeline types: traces

The probabilistic sampler supports two types of sampling:

1. sampling.priority semantic convention as defined by OpenTracing
2. Trace ID hashing

The sampling.priority semantic convention takes priority over trace ID hashing. As the name implies, trace ID hashing samples based on hash values determined by trace IDs. In order for trace ID hashing to work, all collectors for a given tier (e.g. behind the same load balancer) must have the same hash_seed. It is also possible to leverage a different hash_seed at different collector tiers to support additional sampling requirements. Please refer to config.go for the config spec.

The following configuration options can be modified:

• hash_seed (no default): An integer used to compute the hash algorithm. Note that all collectors for a given tier (e.g. behind the same load balancer) should have the same hash_seed.
• sampling_percentage (default = 0): Percentage at which traces are sampled; >= 100 samples all traces

Examples:

processors:
  probabilistic_sampler:
    hash_seed: 22
    sampling_percentage: 15.3

Refer to config.yaml for detailed examples on using the processor.

Documentation

Index

• func NewFactory() component.ProcessorFactory
• type Config
  • func (cfg *Config) Validate() error

Functions

func NewFactory

func NewFactory() component.ProcessorFactory

NewFactory returns a new factory for the Probabilistic sampler processor.

Types

type Config

type Config struct {
	config.ProcessorSettings `mapstructure:",squash"` // squash ensures fields are correctly decoded in embedded struct

	// SamplingPercentage is the percentage rate at which traces are going to be sampled. Defaults to zero, i.e.: no sample.
	// Values greater or equal 100 are treated as "sample all traces".
	SamplingPercentage float32 `mapstructure:"sampling_percentage"`

	// HashSeed allows one to configure the hashing seed. This is important in scenarios where multiple layers of collectors
	// have different sampling rates: if they use the same seed all passing one layer may pass the other even if they have
	// different sampling rates, configuring different seeds avoids that.
	HashSeed uint32 `mapstructure:"hash_seed"`
}

Config has the configuration guiding the trace sampler processor.

func (*Config) Validate

func (cfg *Config) Validate() error

Validate checks if the processor configuration is valid