errorutil: add benchmark for errors.Is

This is to help debug an expensive error handling call path that was
seen in a profile.

Release note: None

Author: rafiss

pkg/util/errorutil/error_test.go

@@ -6,9 +6,13 @@
 package errorutil
 
 import (
+	"context"
 	"fmt"
+	"net"
 	"strings"
 	"testing"
+
+	"github.com/cockroachdb/errors"
 )
 
 // Renumber lines so they're stable no matter what changes above. (We
@@ -39,3 +43,146 @@ func TestUnexpectedWithIssueErrorf(t *testing.T) {
 		t.Errorf("expected substring in error\n%s\ngot:\n%s", exp, safeMsg)
 	}
 }
+
+func BenchmarkErrorsIs(b *testing.B) {
+	b.Run("SimpleError", func(b *testing.B) {
+		err := errors.New("test")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("WrappedError", func(b *testing.B) {
+		baseErr := errors.New("test")
+		err := errors.Wrap(baseErr, "wrapped error")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("WrappedWithStack", func(b *testing.B) {
+		baseErr := errors.New("test")
+		err := errors.WithStack(baseErr)
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("NetworkError", func(b *testing.B) {
+		netErr := &net.OpError{
+			Op:   "dial",
+			Net:  "tcp",
+			Addr: &net.TCPAddr{IP: net.IPv4(127, 0, 0, 1), Port: 26257},
+			Err:  fmt.Errorf("connection refused"),
+		}
+		err := errors.Wrap(netErr, "network connection failed")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("DeeplyWrappedNetworkError", func(b *testing.B) {
+		netErr := &net.OpError{
+			Op:   "dial",
+			Net:  "tcp",
+			Addr: &net.TCPAddr{IP: net.IPv4(127, 0, 0, 1), Port: 26257},
+			Err:  fmt.Errorf("connection refused"),
+		}
+		err := errors.WithStack(netErr)
+		err = errors.Wrap(err, "failed to connect to database")
+		err = errors.Wrap(err, "unable to establish connection")
+		err = errors.WithStack(err)
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("MultipleWrappedErrors", func(b *testing.B) {
+		baseErr := errors.New("internal error")
+		err := errors.WithStack(baseErr)
+		err = errors.Wrap(err, "operation failed")
+		err = errors.WithStack(err)
+		err = errors.Wrap(err, "transaction failed")
+		err = errors.WithStack(err)
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("NetworkErrorWithLongAddress", func(b *testing.B) {
+		netErr := &net.OpError{
+			Op:  "read",
+			Net: "tcp",
+			Addr: &net.TCPAddr{
+				IP:   net.ParseIP("2001:0db8:85a3:0000:0000:8a2e:0370:7334"),
+				Port: 26257,
+			},
+			Err: fmt.Errorf("i/o timeout"),
+		}
+		err := errors.WithStack(netErr)
+		err = errors.Wrap(err, "failed to read from connection")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("WithMessage", func(b *testing.B) {
+		baseErr := errors.New("test")
+		err := errors.WithMessage(baseErr, "additional context")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("MultipleWithMessage", func(b *testing.B) {
+		baseErr := errors.New("internal error")
+		err := errors.WithMessage(baseErr, "first message")
+		err = errors.WithMessage(err, "second message")
+		err = errors.WithMessage(err, "third message")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("WithMessageAndStack", func(b *testing.B) {
+		baseErr := errors.New("test")
+		err := errors.WithStack(baseErr)
+		err = errors.WithMessage(err, "operation context")
+		err = errors.WithStack(err)
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("NetworkErrorWithMessage", func(b *testing.B) {
+		netErr := &net.OpError{
+			Op:   "dial",
+			Net:  "tcp",
+			Addr: &net.TCPAddr{IP: net.IPv4(127, 0, 0, 1), Port: 26257},
+			Err:  fmt.Errorf("connection refused"),
+		}
+		err := errors.WithMessage(netErr, "database connection failed")
+		err = errors.WithMessage(err, "unable to reach server")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+
+	b.Run("NetworkErrorWithEverything", func(b *testing.B) {
+		netErr := &net.OpError{
+			Op:   "dial",
+			Net:  "tcp",
+			Addr: &net.TCPAddr{IP: net.IPv4(127, 0, 0, 1), Port: 26257},
+			Err:  fmt.Errorf("connection refused"),
+		}
+		err := errors.WithStack(netErr)
+		err = errors.WithMessage(err, "database connection failed")
+		err = errors.Wrap(err, "failed to establish TCP connection")
+		err = errors.WithStack(err)
+		err = errors.WithMessage(err, "unable to reach CockroachDB server")
+		err = errors.Wrap(err, "connection attempt failed")
+		for range b.N {
+			errors.Is(err, context.Canceled)
+		}
+	})
+}