diff --git a/internal/state/manager.go b/internal/state/manager.go
index b80ec54..5734632 100644
--- a/internal/state/manager.go
+++ b/internal/state/manager.go
@@ -204,9 +204,11 @@ func (m *Manager) Get(ip string) (*Device, bool) {
 func (m *Manager) GetAll() []Device {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
-	result := make([]Device, 0, len(m.devices))
+	result := make([]Device, len(m.devices))
+	i := 0
 	for _, dev := range m.devices {
-		result = append(result, *dev)
+		result[i] = *dev
+		i++
 	}
 	return result
 }
@@ -245,9 +247,11 @@ func (m *Manager) UpdateDeviceSNMP(ip, hostname, sysDescr string) {
 func (m *Manager) GetAllIPs() []string {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
-	ips := make([]string, 0, len(m.devices))
+	ips := make([]string, len(m.devices))
+	i := 0
 	for ip := range m.devices {
-		ips = append(ips, ip)
+		ips[i] = ip
+		i++
 	}
 	return ips
 }
diff --git a/internal/state/manager_bench_test.go b/internal/state/manager_bench_test.go
index 124543f..bd7fd4e 100644
--- a/internal/state/manager_bench_test.go
+++ b/internal/state/manager_bench_test.go
@@ -419,3 +419,34 @@ func BenchmarkConcurrentMixed(b *testing.B) {
 		})
 	}
 }
+
+// BenchmarkGetAll tests the performance of retrieving all devices
+func BenchmarkGetAll(b *testing.B) {
+	benchmarks := []struct {
+		name        string
+		deviceCount int
+	}{
+		{"GetAll_100devices", 100},
+		{"GetAll_1Kdevices", 1000},
+		{"GetAll_10Kdevices", 10000},
+		{"GetAll_20Kdevices", 20000},
+	}
+
+	for _, bm := range benchmarks {
+		b.Run(bm.name, func(b *testing.B) {
+			mgr := NewManager(bm.deviceCount * 2)
+
+			// Populate with devices
+			for i := 0; i < bm.deviceCount; i++ {
+				ip := fmt.Sprintf("192.168.%d.%d", i/256, i%256)
+				mgr.AddDevice(ip)
+			}
+
+			b.ResetTimer()
+
+			for i := 0; i < b.N; i++ {
+				_ = mgr.GetAll()
+			}
+		})
+	}
+}