[management] Improve mgmt sync performance (#2363)

management/server/peer/peer.go

@@ -1,7 +1,6 @@
 package peer
 
 import (
-	"fmt"
 	"net"
 	"net/netip"
 	"slices"
@@ -241,7 +240,7 @@ func (p *Peer) FQDN(dnsDomain string) string {
 	if dnsDomain == "" {
 		return ""
 	}
-	return fmt.Sprintf("%s.%s", p.DNSLabel, dnsDomain)
+	return p.DNSLabel + "." + dnsDomain
 }
 
 // EventMeta returns activity event meta related to the peer

management/server/peer/peer_test.go

@@ -0,0 +1,31 @@
+package peer
+
+import (
+	"fmt"
+	"testing"
+)
+
+// FQDNOld is the original implementation for benchmarking purposes
+func (p *Peer) FQDNOld(dnsDomain string) string {
+	if dnsDomain == "" {
+		return ""
+	}
+	return fmt.Sprintf("%s.%s", p.DNSLabel, dnsDomain)
+}
+
+func BenchmarkFQDN(b *testing.B) {
+	p := &Peer{DNSLabel: "test-peer"}
+	dnsDomain := "example.com"
+
+	b.Run("Old", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			p.FQDNOld(dnsDomain)
+		}
+	})
+
+	b.Run("New", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			p.FQDN(dnsDomain)
+		}
+	})
+}