iOS App Launch Optimizasyonu: %70 Hızlandırma Rehberi

1// ❌ KÖTÜ - +load metodları pre-main'i yavaşlatır
2@objc class LegacyManager: NSObject {
3    override class func load() {
4        // Bu kod main() öncesi çalışır - KAÇININ!
5        setupLogging()
6        configureAnalytics()
7    }
8}
9 
10// ✅ İYİ - Lazy initialization
11@objc class ModernManager: NSObject {
12    static let shared = ModernManager()
13    
14    private init() {
15        // İlk erişimde çalışır
16        setupLogging()
17        configureAnalytics()
18    }
19}

1// ❌ KÖTÜ - Senkron initialization
2@main
3struct MyApp: App {
4    init() {
5        // Ana thread'i bloklayan işlemler
6        FirebaseApp.configure()  // ~200ms
7        Crashlytics.configure()  // ~100ms
8        Analytics.configure()    // ~150ms
9        // Toplam: ~450ms bekleme!
10    }
11    
12    var body: some Scene {
13        WindowGroup {
14            ContentView()
15        }
16    }
17}
18 
19// ✅ İYİ - Async initialization
20@main
21struct MyApp: App {
22    @State private var isInitialized = false
23    
24    init() {
25        // Sadece kritik setup
26        configureAppearance()
27    }
28    
29    var body: some Scene {
30        WindowGroup {
31            if isInitialized {
32                ContentView()
33            } else {
34                SplashView()
35                    .task {
36                        await initializeServices()
37                        isInitialized = true
38                    }
39            }
40        }
41    }
42    
43    private func initializeServices() async {
44        // Parallel initialization
45        async let firebase = Task { FirebaseApp.configure() }
46        async let crash = Task { Crashlytics.configure() }
47        async let analytics = Task { Analytics.configure() }
48        
49        _ = await (firebase, crash, analytics)
50    }
51}

1// Xcode -> Build Settings -> 
2// "Dead Code Stripping" = YES
3// "Link-Time Optimization" = YES
4 
5// Package.swift - Sadece gereken modüller
6dependencies: [
7    // ❌ Tüm Firebase
8    // .package(url: "firebase-ios-sdk", from: "10.0.0"),
9    
10    // ✅ Sadece gerekli modüller
11    .product(name: "FirebaseAnalytics", package: "firebase-ios-sdk"),
12    .product(name: "FirebaseAuth", package: "firebase-ios-sdk"),
13]

1// Package.swift
2let package = Package(
3    name: "MyApp",
4    products: [
5        // Static linking - daha hızlı launch
6        .library(name: "Core", type: .static, targets: ["Core"]),
7    ],
8    targets: [
9        .target(name: "Core"),
10    ]
11)

1struct HomeView: View {
2    @State private var isLoading = true
3    @State private var data: HomeData?
4    
5    var body: some View {
6        Group {
7            if isLoading {
8                HomeSkeletonView()
9            } else if let data = data {
10                HomeContentView(data: data)
11            }
12        }
13        .task {
14            // Kritik data'yı önce yükle
15            data = await loadCriticalData()
16            isLoading = false
17            
18            // Diğer data'ları background'da
19            Task.detached(priority: .background) {
20                await preloadSecondaryData()
21            }
22        }
23    }
24}
25 
26struct HomeSkeletonView: View {
27    var body: some View {
28        VStack(spacing: 16) {
29            // Header skeleton
30            RoundedRectangle(cornerRadius: 8)
31                .fill(.gray.opacity(0.3))
32                .frame(height: 60)
33                .shimmer()
34            
35            // Content skeletons
36            ForEach(0..<5) { _ in
37                RoundedRectangle(cornerRadius: 12)
38                    .fill(.gray.opacity(0.3))
39                    .frame(height: 100)
40                    .shimmer()
41            }
42        }
43        .padding()
44    }
45}
46 
47// Shimmer effect
48struct ShimmerModifier: ViewModifier {
49    @State private var phase: CGFloat = 0
50    
51    func body(content: Content) -> some View {
52        content
53            .overlay(
54                LinearGradient(
55                    colors: [.clear, .white.opacity(0.5), .clear],
56                    startPoint: .leading,
57                    endPoint: .trailing
58                )
59                .offset(x: phase)
60            )
61            .mask(content)
62            .onAppear {
63                withAnimation(.linear(duration: 1.5).repeatForever(autoreverses: false)) {
64                    phase = 400
65                }
66            }
67    }
68}

1import MetricKit
2 
3class LaunchMetricsManager: NSObject, MXMetricManagerSubscriber {
4    static let shared = LaunchMetricsManager()
5    
6    func startCollecting() {
7        MXMetricManager.shared.add(self)
8    }
9    
10    func didReceive(_ payloads: [MXMetricPayload]) {
11        for payload in payloads {
12            if let launchMetrics = payload.applicationLaunchMetrics {
13                let histogram = launchMetrics.histogrammedTimeToFirstDraw
14                
15                // Analytics'e gönder
16                Analytics.log(
17                    event: "launch_time",
18                    params: [
19                        "p50": histogram.bucketEnumerator.allObjects[50],
20                        "p95": histogram.bucketEnumerator.allObjects[95],
21                        "p99": histogram.bucketEnumerator.allObjects[99]
22                    ]
23                )
24            }
25        }
26    }
27}

1import os.signpost
2 
3// Launch time olcum icin dedicated log
4private let launchLog = OSLog(subsystem: "com.myapp", category: "Launch")
5 
6@main
7struct MyApp: App {
8    init() {
9        // Launch baslangicindan itibaren olcumu baslat
10        os_signpost(.begin, log: launchLog, name: "AppLaunch")
11    }
12 
13    var body: some Scene {
14        WindowGroup {
15            ContentView()
16                .onAppear {
17                    // Ilk frame renderlandiginda olcumu bitir
18                    os_signpost(.end, log: launchLog, name: "AppLaunch")
19                    reportLaunchTime()
20                }
21        }
22    }
23 
24    private func reportLaunchTime() {
25        let launchTime = CFAbsoluteTimeGetCurrent() - processStartTime
26 
27        // Backend'e gonder
28        Analytics.shared.track(.launchTime(
29            duration: launchTime,
30            type: isWarmLaunch ? .warm : .cold,
31            device: UIDevice.current.model,
32            osVersion: UIDevice.current.systemVersion
33        ))
34    }
35}

1import XCTest
2 
3final class LaunchPerformanceTests: XCTestCase {
4    func testColdLaunchTime() throws {
5        // Cold launch performance testi
6        measure(metrics: [XCTApplicationLaunchMetric()]) {
7            XCUIApplication().launch()
8        }
9    }
10 
11    func testColdLaunchUnder2Seconds() throws {
12        let app = XCUIApplication()
13        let startTime = CFAbsoluteTimeGetCurrent()
14        app.launch()
15        let elapsed = CFAbsoluteTimeGetCurrent() - startTime
16 
17        XCTAssertLessThan(elapsed, 2.0,
18            "Cold launch 2 saniyenin altinda olmali, simdiki: \(elapsed)s")
19    }
20}