traceprof

Documentation

Overview

Package traceprof contains shared logic for cross-cutting tracer/profiler features.

Index

• Constants
• type EndpointCounter
  • func GlobalEndpointCounter() *EndpointCounter
  • func NewEndpointCounter(limit int) *EndpointCounter
  • func (e *EndpointCounter) GetAndReset() map[string]uint64
  • func (e *EndpointCounter) Inc(endpoint string)
  • func (e *EndpointCounter) SetEnabled(enabled bool) bool

Constants

const (
	SpanID          = "span id"
	LocalRootSpanID = "local root span id"
	TraceEndpoint   = "trace endpoint"
)

pprof labels applied by the tracer to show up in the profiler's profiles.

const (
	CodeHotspotsEnvVar  = "DD_PROFILING_CODE_HOTSPOTS_COLLECTION_ENABLED" // aka code hotspots
	EndpointEnvVar      = "DD_PROFILING_ENDPOINT_COLLECTION_ENABLED"      // aka endpoint profiling
	EndpointCountEnvVar = "DD_PROFILING_ENDPOINT_COUNT_ENABLED"           // aka unit of work
)

env variables used to control cross-cutting tracer/profiling features.

Types

type EndpointCounter

type EndpointCounter struct {
	// contains filtered or unexported fields
}

EndpointCounter counts hits per endpoint.

TODO: This is a naive implementation with poor performance, e.g. 125ns/op in BenchmarkEndpointCounter on M1. We can do 10-20x better with something more complicated [1]. This will be done in a follow-up PR. [1] https://github.com/felixge/countermap/blob/main/xsync_map_counter_map.go

func GlobalEndpointCounter

func GlobalEndpointCounter() *EndpointCounter

GlobalEndpointCounter returns the endpoint counter that is shared between tracing and profiling to support the unit of work feature.

func NewEndpointCounter

func NewEndpointCounter(limit int) *EndpointCounter

NewEndpointCounter returns a new NewEndpointCounter that will track hit counts for up to limit endpoints. A limit of <= 0 indicates no limit.

func (*EndpointCounter) GetAndReset

func (e *EndpointCounter) GetAndReset() map[string]uint64

GetAndReset returns the hit counts for all endpoints and resets their counts back to 0.

func (*EndpointCounter) Inc

func (e *EndpointCounter) Inc(endpoint string)

Inc increments the hit counter for the given endpoint by 1. If endpoint counting is disabled, this method does nothing and is almost zero-cost.

func (*EndpointCounter) SetEnabled

func (e *EndpointCounter) SetEnabled(enabled bool) bool

SetEnabled changes if endpoint counting is enabled or not. The previous value is returned.