enhance: simple head samplers for ratio and rate limit

go-vela · Aug 21, 2024 · e590f23 · e590f23
1 parent d921b3e
commit e590f23
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Showing 4 changed files with 19 additions and 9 deletions.
diff --git a/docker-compose.yml b/docker-compose.yml
@@ -46,8 +46,9 @@ services:
       VELA_SCHEDULE_ALLOWLIST: '*'
       VELA_ENABLE_TRACING: true
       VELA_TRACING_SERVICE_NAME: 'vela-server'
+      VELA_TRACING_SAMPLE_RATIO: 1
+      VELA_TRACING_SAMPLE_RATELIMIT_PER_SECOND: 1
       OTEL_EXPORTER_OTLP_ENDPOINT: http://jaeger:4318
-      VELA_TRACING_SAMPLER_RATIO: 1
     env_file:
       - .env
     restart: always

diff --git a/tracing/flags.go b/tracing/flags.go
@@ -22,9 +22,15 @@ var Flags = []cli.Flag{
 		Value:   "vela-server",
 	},
 	&cli.Float64Flag{
-		EnvVars: []string{"VELA_TRACING_SAMPLER_RATIO", "TRACING_SAMPLER_RATIO"},
-		Name:    "tracing.sampler.ratio",
-		Usage:   "set otel tracing sampler ratio. see: https://opentelemetry.io/docs/concepts/sampling/",
+		EnvVars: []string{"VELA_TRACING_SAMPLE_RATIO", "OTEL_TRACE_SAMPLE_RATIO"},
+		Name:    "tracing.sample.ratio",
+		Usage:   "set otel tracing head-sampler acceptance ratio. see: https://opentelemetry.io/docs/concepts/sampling/",
 		Value:   0.5,
 	},
+	&cli.Float64Flag{
+		EnvVars: []string{"VELA_TRACING_SAMPLE_RATELIMIT_PER_SECOND", "OTEL_TRACING_SAMPLE_RATELIMIT_PER_SECOND"},
+		Name:    "tracing.sample.persecond",
+		Usage:   "set otel tracing head-sampler rate-limiting to N per second. see: https://opentelemetry.io/docs/concepts/sampling/",
+		Value:   1,
+	},
 }
diff --git a/tracing/sampler/sampler.go b/tracing/sampler/sampler.go
@@ -24,7 +24,7 @@ type rateLimitSampler struct {
 	limiter      *rate.Limiter
 }
 
-func newRateLimitSampler(perSec float64) *rateLimitSampler {
+func NewRateLimitSampler(perSec float64) *rateLimitSampler {
 	return &rateLimitSampler{
 		maxPerSecond: perSec,
 		limiter:      rate.NewLimiter(rate.Every(time.Duration(1.0/perSec)*time.Second), 1),

diff --git a/tracing/tracer.go b/tracing/tracer.go
@@ -5,6 +5,7 @@ package tracing
 import (
 	"context"
 
+	"github.com/go-vela/server/tracing/sampler"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
 	"go.opentelemetry.io/otel"
@@ -34,12 +35,14 @@ func initTracer(c *cli.Context) (*sdktrace.TracerProvider, error) {
 		return nil, err
 	}
 
-	logrus.Info("intializing tracing using sampler ratio: ", c.Float64("tracing.sampler.ratio"))
+	logrus.Infof("intializing tracing using samplers: ratio(%f), persecond(%f)", c.Float64("tracing.sampler.ratio"), c.Float64("tracing.sampler.persecond"))
+
+	ratioSampler := sdktrace.ParentBased(sdktrace.TraceIDRatioBased(c.Float64("tracing.sampler.ratio")))
+	rateLimitSampler := sdktrace.ParentBased(sampler.NewRateLimitSampler(c.Float64("tracing.sampler.persecond")))
 
 	tp := sdktrace.NewTracerProvider(
-		// sdktrace.WithSampler(sdktrace.AlwaysSample()),
-		sdktrace.WithSampler(sdktrace.ParentBased(sdktrace.TraceIDRatioBased(c.Float64("tracing.sampler.ratio")))),
-		// sdktrace.WithSampler(sdktrace.RateLimiting(1000, 1000)),
+		sdktrace.WithSampler(ratioSampler),
+		sdktrace.WithSampler(rateLimitSampler),
 		sdktrace.WithBatcher(exporter),
 		sdktrace.WithResource(res),
 	)