perf: Compare different span creation scenarios

opentelemetry-sdk/Cargo.toml

@@ -85,6 +85,10 @@ required-features = ["experimental_metrics_custom_reader"]
 name = "trace"
 harness = false
 
+[[bench]]
+name = "span"
+harness = false
+
 [[bench]]
 name = "log_processor"
 harness = false

opentelemetry-sdk/benches/span.rs

@@ -0,0 +1,179 @@
+/*
+    Span Creation scenarios.
+    This benchmark measures the performance cost of different
+    span creation patterns in OpenTelemetry when using On/Off
+    sampling strategies.
+
+    TODO: Cover the impact of the presence of ActiveSpan in the context.
+
+    The benchmark results:
+    criterion = "0.5.1"
+    rustc 1.83.0 (90b35a623 2024-11-26)
+    Hardware: M4Pro
+    | Test                                                  | Always Sample | Never Sample |
+    |-------------------------------------------------------|---------------|--------------|
+    | span-creation-simple                                  | 236.38 ns     | 77.155 ns    |
+    | span-creation-span-builder                            | 234.48 ns     | 109.22 ns    |
+    | span-creation-tracer-in-span                          | 417.24 ns     | 221.93 ns    |
+    | span-creation-simple-context-activation               | 408.40 ns     | 59.426 ns    |
+    | span-creation-span-builder-context-activation         | 414.39 ns     | 90.575 ns    |
+*/
+
+use criterion::{criterion_group, criterion_main, Criterion};
+use opentelemetry::{
+    trace::{mark_span_as_active, Span, TraceContextExt, Tracer, TracerProvider},
+    Context, KeyValue,
+};
+use opentelemetry_sdk::{
+    error::OTelSdkResult,
+    trace::{self as sdktrace, SpanData, SpanExporter},
+};
+#[cfg(not(target_os = "windows"))]
+use pprof::criterion::{Output, PProfProfiler};
+
+fn criterion_benchmark(c: &mut Criterion) {
+    trace_benchmark_group(c, "span-creation-simple", |tracer| {
+        // Simple span creation
+        // There is not ability to specify anything other than the name.
+        // Attributes are set after creation, and automatically gets
+        // ignored if sampling is unfavorable.
+        let mut span = tracer.start("span-name");
+        span.set_attribute(KeyValue::new("key1", false));
+        span.set_attribute(KeyValue::new("key2", "hello"));
+        span.set_attribute(KeyValue::new("key3", 123.456));
+        span.set_attribute(KeyValue::new("key4", "world"));
+        span.set_attribute(KeyValue::new("key5", 123));
+        span.end();
+    });
+
+    trace_benchmark_group(c, "span-creation-span-builder", |tracer| {
+        // This is similar to the simple span creation, but allows
+        // attributes and other properties to be set during creation.
+        // It is slightly slower than the simple span creation due to the fact that
+        // attributes are collected into a vec! and allocated, even before sampling
+        // decision is made.
+        let mut span = tracer
+            .span_builder("span-name")
+            .with_attributes([
+                KeyValue::new("key1", false),
+                KeyValue::new("key2", "hello"),
+                KeyValue::new("key3", 123.456),
+            ])
+            .start(tracer);
+        span.set_attribute(KeyValue::new("key4", "world"));
+        span.set_attribute(KeyValue::new("key5", 123));
+        span.end();
+    });
+
+    trace_benchmark_group(c, "span-creation-tracer-in-span", |tracer| {
+        // This is similar to the simple span creation, but also does the job of activating
+        // the span in the current context.
+        // It is slower than other approaches of activation due to the fact that
+        // context activation is done, irrespective of sampling decision.
+        tracer.in_span("span-name", |ctx| {
+            let span = ctx.span();
+            span.set_attribute(KeyValue::new("key1", false));
+            span.set_attribute(KeyValue::new("key2", "hello"));
+            span.set_attribute(KeyValue::new("key3", 123.456));
+            span.set_attribute(KeyValue::new("key4", "world"));
+            span.set_attribute(KeyValue::new("key5", 123));
+        });
+    });
+
+    trace_benchmark_group(c, "span-creation-simple-context-activation", |tracer| {
+        // This optimizes by bypassing the context activation
+        // based on sampling decision, and hence it is faster than the
+        // tracer.in_span approach.
+        let mut span = tracer.start("span-name");
+        span.set_attribute(KeyValue::new("key1", false));
+        span.set_attribute(KeyValue::new("key2", "hello"));
+        span.set_attribute(KeyValue::new("key3", 123.456));
+        if span.is_recording() {
+            let _guard = mark_span_as_active(span);
+            Context::map_current(|cx| {
+                let span_from_context = cx.span();
+                span_from_context.set_attribute(KeyValue::new("key4", "world"));
+                span_from_context.set_attribute(KeyValue::new("key5", 123));
+            });
+        }
+    });
+
+    trace_benchmark_group(
+        c,
+        "span-creation-span-builder-context-activation",
+        |tracer| {
+            // This optimizes by bypassing the context activation
+            // based on sampling decision, and hence it is faster than the
+            // tracer.in_span approach.
+            let span = tracer
+                .span_builder("span-name")
+                .with_attributes([
+                    KeyValue::new("key1", false),
+                    KeyValue::new("key2", "hello"),
+                    KeyValue::new("key3", 123.456),
+                ])
+                .start(tracer);
+            if span.is_recording() {
+                let _guard = mark_span_as_active(span);
+                Context::map_current(|cx| {
+                    let span_from_context = cx.span();
+                    span_from_context.set_attribute(KeyValue::new("key4", "world"));
+                    span_from_context.set_attribute(KeyValue::new("key5", 123));
+                });
+            }
+        },
+    );
+}
+
+#[derive(Debug)]
+struct VoidExporter;
+
+impl SpanExporter for VoidExporter {
+    async fn export(&self, _spans: Vec<SpanData>) -> OTelSdkResult {
+        Ok(())
+    }
+}
+
+fn trace_benchmark_group<F: Fn(&sdktrace::SdkTracer)>(c: &mut Criterion, name: &str, f: F) {
+    let mut group = c.benchmark_group(name);
+
+    group.bench_function("always-sample", |b| {
+        let provider = sdktrace::SdkTracerProvider::builder()
+            .with_sampler(sdktrace::Sampler::AlwaysOn)
+            .with_simple_exporter(VoidExporter)
+            .build();
+        let always_sample = provider.tracer("always-sample");
+
+        b.iter(|| f(&always_sample));
+    });
+
+    group.bench_function("never-sample", |b| {
+        let provider = sdktrace::SdkTracerProvider::builder()
+            .with_sampler(sdktrace::Sampler::AlwaysOff)
+            .with_simple_exporter(VoidExporter)
+            .build();
+        let never_sample = provider.tracer("never-sample");
+        b.iter(|| f(&never_sample));
+    });
+
+    group.finish();
+}
+
+#[cfg(not(target_os = "windows"))]
+criterion_group! {
+    name = benches;
+    config = Criterion::default()
+        .warm_up_time(std::time::Duration::from_secs(1))
+        .measurement_time(std::time::Duration::from_secs(2))
+        .with_profiler(PProfProfiler::new(100, Output::Flamegraph(None)));
+    targets = criterion_benchmark
+}
+#[cfg(target_os = "windows")]
+criterion_group! {
+    name = benches;
+    config = Criterion::default()
+        .warm_up_time(std::time::Duration::from_secs(1))
+        .measurement_time(std::time::Duration::from_secs(2));
+    targets = criterion_benchmark
+}
+criterion_main!(benches);