opt: downloader (#1019)

* refactor: download limiter * opt: Decrease the time interval for replenishing tokens * fix: crash by NumberBox possibly being -21e * Improve more precise speed limits Co-authored-by: DismissedLight <[email protected]> * opt: reduce downloader writes * refactor: simplify rate limiting --------- Co-authored-by: DismissedLight <[email protected]> Co-authored-by: Scighost <[email protected]>
Scighost · Sep 15, 2024 · 93c028d · 93c028d
1 parent 0731321
commit 93c028d
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Showing 6 changed files with 106 additions and 50 deletions.
diff --git a/src/Starward/Pages/Setting/DownloadSettingPage.xaml b/src/Starward/Pages/Setting/DownloadSettingPage.xaml
@@ -85,6 +85,7 @@
                         Spacing="12">
                 <NumberBox MinWidth="100"
                            Minimum="0"
+                           Maximum="2097151"
                            Value="{x:Bind SpeedLimit, Mode=TwoWay}" />
                 <TextBlock VerticalAlignment="Center" Text="KB/s" />
             </StackPanel>

diff --git a/src/Starward/Pages/Setting/DownloadSettingPage.xaml.cs b/src/Starward/Pages/Setting/DownloadSettingPage.xaml.cs
@@ -5,6 +5,7 @@
 using Starward.Services.Download;
 using System;
 using System.IO;
+using System.Threading;
 using System.Threading.Tasks;
 using Windows.Storage;
 using Windows.System;
@@ -69,8 +70,10 @@ partial void OnDefaultInstallPathChanged(string? value)
     private int speedLimit = AppConfig.SpeedLimitKBPerSecond;
     partial void OnSpeedLimitChanged(int value)
     {
-        InstallGameManager.SetRateLimit(value * 1024);
+        int speed = value <= 0 ? int.MaxValue : value * 1024;
+        Interlocked.Exchange(ref InstallGameManager.SpeedLimitBytesPerSecond, speed);
         AppConfig.SpeedLimitKBPerSecond = value;
+        InstallGameManager.SetRateLimit();
     }
 
 

diff --git a/src/Starward/Services/Download/InstallGameManager.cs b/src/Starward/Services/Download/InstallGameManager.cs
@@ -1,10 +1,11 @@
-using CommunityToolkit.Mvvm.Messaging;
+using CommunityToolkit.Mvvm.Messaging;
 using Starward.Core;
 using Starward.Helpers;
 using Starward.Messages;
 using System;
 using System.Collections.Concurrent;
 using System.Diagnostics.CodeAnalysis;
+using System.Threading;
 using System.Threading.RateLimiting;
 
 namespace Starward.Services.Download;
@@ -19,7 +20,9 @@ internal class InstallGameManager
     private InstallGameManager()
     {
         _services = new();
-        SetRateLimit(AppConfig.SpeedLimitKBPerSecond * 1024);
+        int speed = AppConfig.SpeedLimitKBPerSecond * 1024;
+        SpeedLimitBytesPerSecond = speed == 0 ? int.MaxValue : speed;
+        SetRateLimit();
     }
 
 
@@ -31,32 +34,13 @@ private InstallGameManager()
 
 
 
-    public static TokenBucketRateLimiter RateLimiter { get; private set; }
-
+    public static long SpeedLimitBytesPerSecond;
 
 
-    public static void SetRateLimit(int bytesPerSecond)
-    {
-        if (bytesPerSecond <= 0)
-        {
-            bytesPerSecond = int.MaxValue;
-        }
-        else if (bytesPerSecond < (1 << 14))
-        {
-            bytesPerSecond = 1 << 14;
-        }
-        RateLimiter = new TokenBucketRateLimiter(new TokenBucketRateLimiterOptions
-        {
-            TokenLimit = bytesPerSecond,
-            ReplenishmentPeriod = TimeSpan.FromSeconds(1),
-            TokensPerPeriod = bytesPerSecond,
-            QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
-            AutoReplenishment = true
-        });
-    }
-
+    public static TokenBucketRateLimiter RateLimiter { get; private set; }
 
 
+    public static bool IsEnableSpeedLimit => Interlocked.Read(ref SpeedLimitBytesPerSecond) != int.MaxValue;
 
 
     public event EventHandler<InstallGameStateModel> InstallTaskAdded;
@@ -68,6 +52,23 @@ public static void SetRateLimit(int bytesPerSecond)
 
 
 
+    public static void SetRateLimit()
+    {
+        var speedLimitBytesPerPeriod = (int)SpeedLimitBytesPerSecond / 25;
+        RateLimiter = new TokenBucketRateLimiter(new TokenBucketRateLimiterOptions
+        {
+            TokenLimit = speedLimitBytesPerPeriod,
+            // 0.04: 将每秒切割为上面的25份，间隔越小速度越精准。
+            // 因补充令牌逻辑运行耗时远大于期望，若间隔极小，将无法达到最高限速。
+            ReplenishmentPeriod = TimeSpan.FromSeconds(0.04),
+            TokensPerPeriod = speedLimitBytesPerPeriod,
+            QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
+            AutoReplenishment = true
+        });
+    }
+
+
+
     public bool TryGetInstallService(GameBiz gameBiz, [NotNullWhen(true)] out InstallGameService? service)
     {
         if (_services.TryGetValue(gameBiz, out var model))

diff --git a/src/Starward/Services/Download/InstallGameService.cs b/src/Starward/Services/Download/InstallGameService.cs
@@ -1,4 +1,4 @@
-using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging;
 using Starward.Core;
 using Starward.Core.HoYoPlay;
 using Starward.Services.InstallGame;
@@ -21,7 +21,6 @@
 using System.Text;
 using System.Text.Json.Nodes;
 using System.Threading;
-using System.Threading.RateLimiting;
 using System.Threading.Tasks;
 using Vanara.PInvoke;
 
@@ -625,6 +624,12 @@ public void ClearState()
 
 
 
+
+    protected List<Task> _taskItems;
+    public List<Task> TaskItems => _taskItems;
+
+
+
     protected void StartTask(InstallGameState state)
     {
         if (_concurrentExecuteThreadCount > 0) return;
@@ -715,7 +720,6 @@ protected void StartTask(InstallGameState state)
             _finishBytes = 0;
         }
         State = state;
-
         _ = RunTasksAsync(); //不需要ConfigureAwait，因为返回值丢弃，且无需调用“.GetAwaiter().OnCompleted()”
         return;
 
@@ -1164,13 +1168,14 @@ protected async Task ExecuteTaskItemAsync(CancellationToken cancellationToken =
                     _installItemQueue.Enqueue(item);
                     return;
                 }
+                catch (Exception ex)
+                {
+                    _logger.LogError(ex, nameof(ExecuteTaskItemAsync));
+                    _installItemQueue.Enqueue(item);
+                    OnInstallFailed(ex);
+                }
             }
         }
-        catch (Exception ex)
-        {
-            _logger.LogError(ex, nameof(ExecuteTaskItemAsync));
-            OnInstallFailed(ex);
-        }
         finally
         {
             Interlocked.Decrement(ref _concurrentExecuteThreadCount);
@@ -1182,7 +1187,7 @@ protected async Task ExecuteTaskItemAsync(CancellationToken cancellationToken =
 
     protected async Task DownloadItemAsync(InstallGameItem item, CancellationToken cancellationToken = default)
     {
-        const int BUFFER_SIZE = 1 << 10;
+        const int BUFFER_SIZE = 1 << 14;
         string file = item.Path;
         string file_tmp = item.Path + "_tmp";
         string file_target;
@@ -1214,12 +1219,12 @@ protected async Task DownloadItemAsync(InstallGameItem item, CancellationToken c
                 int length;
                 while ((length = await hs.ReadAsync(buffer, cancellationToken).ConfigureAwait(false)) != 0)
                 {
-                    RateLimitLease lease = await InstallGameManager.RateLimiter.AcquireAsync(length, cancellationToken).ConfigureAwait(false);
-                    while (!lease.IsAcquired)
-                    {
-                        await Task.Delay(1, cancellationToken).ConfigureAwait(false);
-                        lease = await InstallGameManager.RateLimiter.AcquireAsync(length, cancellationToken).ConfigureAwait(false);
-                    }
+                    int totalTokens = 0;
+                    while (InstallGameManager.IsEnableSpeedLimit && totalTokens < length)
+                        if (!TokenBucketRateLimiterExtension.TryAcquire(InstallGameManager.RateLimiter, length - totalTokens, out int tokensAcquired, out _))
+                            await Task.Delay(1, cancellationToken).ConfigureAwait(false);
+                        else
+                            totalTokens += tokensAcquired;
                     await fs.WriteAsync(buffer.AsMemory(0, length), cancellationToken).ConfigureAwait(false);
                     Interlocked.Add(ref _finishBytes, length);
                 }

diff --git a/src/Starward/Services/Download/InstallGameStateModel.cs b/src/Starward/Services/Download/InstallGameStateModel.cs
@@ -1,9 +1,12 @@
-using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using Starward.Core;
 using Starward.Models;
 using System;
+using System.Linq;
+using System.Collections.Generic;
 using System.Diagnostics;
+using System.Threading.Tasks;
 
 namespace Starward.Services.Download;
 
@@ -95,15 +98,21 @@ internal InstallGameStateModel(InstallGameService service)
 
     public double _speedBytesPerSecond;
 
+    private List<double> _recentSpeed = [];
+
 
 
     [RelayCommand]
     private void ContinueOrPause()
     {
         if (ButtonGlyph is PlayGlyph)
         {
-            Service.Continue();
-            InstallStarted?.Invoke(this, EventArgs.Empty);
+            Task.Run(() =>
+            {
+                Task.WhenAll(Service.TaskItems).Wait();
+                Service.Continue();
+                InstallStarted?.Invoke(this, EventArgs.Empty);
+            });
         }
         else if (ButtonGlyph is PauseGlyph)
         {
@@ -215,6 +224,7 @@ private void ComputeSpeed(InstallGameState state)
             if (ts - _lastTimestamp >= Stopwatch.Frequency)
             {
                 long bytes = Service.FinishBytes;
+                double averageSpeed = 0;
                 _speedBytesPerSecond = Math.Clamp((double)(bytes - _lastFinishedBytes) / (ts - _lastTimestamp) * Stopwatch.Frequency, 0, long.MaxValue);
                 _lastFinishedBytes = bytes;
                 _lastTimestamp = ts;
@@ -225,22 +235,34 @@ private void ComputeSpeed(InstallGameState state)
                 }
                 else
                 {
-                    if (_speedBytesPerSecond >= MB)
+                    if (_speedBytesPerSecond == 0)
                     {
-                        SpeedText = $"{_speedBytesPerSecond / MB:F2} MB/s";
+                        RemainingTimeText = null;
                     }
                     else
                     {
-                        SpeedText = $"{_speedBytesPerSecond / KB:F2} KB/s";
+                        if (InstallGameManager.IsEnableSpeedLimit)
+                        {
+                            _recentSpeed.RemoveAll(value => Math.Abs(value - _speedBytesPerSecond) / _speedBytesPerSecond > 0.05);
+                            _recentSpeed.RemoveRange(0, Math.Max(_recentSpeed.Count - 59, 0));
+                        }
+                        else
+                        {
+                            _recentSpeed.RemoveAll(value => Math.Abs(value - _speedBytesPerSecond) / _speedBytesPerSecond > 0.25);
+                            _recentSpeed.RemoveRange(0, Math.Max(_recentSpeed.Count - 9, 0));
+                        }
+                        _recentSpeed.Add(_speedBytesPerSecond);
+                        averageSpeed = _recentSpeed.Average();
+                        var seconds = (Service.TotalBytes - Service.FinishBytes) / averageSpeed;
+                        RemainingTimeText = TimeSpan.FromSeconds(seconds).ToString(@"hh\:mm\:ss");
                     }
-                    if (_speedBytesPerSecond == 0)
+                    if (_speedBytesPerSecond >= MB)
                     {
-                        RemainingTimeText = null;
+                        SpeedText = $"{averageSpeed / MB:F2} MB/s";
                     }
                     else
                     {
-                        var seconds = (Service.TotalBytes - Service.FinishBytes) / _speedBytesPerSecond;
-                        RemainingTimeText = TimeSpan.FromSeconds(seconds).ToString(@"hh\:mm\:ss");
+                        SpeedText = $"{averageSpeed / KB:F2} KB/s";
                     }
                 }
             }

diff --git a/src/Starward/Services/Download/TokenBucketRateLimiterExtension.cs b/src/Starward/Services/Download/TokenBucketRateLimiterExtension.cs
@@ -0,0 +1,24 @@
+using System;
+using System.Threading;
+using System.Threading.RateLimiting;
+using System.Runtime.CompilerServices;
+
+namespace Starward.Services.Download;
+
+internal static class TokenBucketRateLimiterExtension
+{
+    public static bool TryAcquire(this TokenBucketRateLimiter rateLimiter, int permits, out int acquired, out TimeSpan retryAfter)
+    {
+        acquired = Math.Min(permits, (int)Volatile.Read(ref PrivateGetTokenCount(rateLimiter)));
+        lock (PrivateGetLock(rateLimiter))
+            return !rateLimiter.AttemptAcquire(acquired).TryGetMetadata(MetadataName.RetryAfter, out retryAfter);
+    }
+
+    // private object Lock → _queue
+    [UnsafeAccessor(UnsafeAccessorKind.Method, Name = "get_Lock")]
+    private static extern object PrivateGetLock(TokenBucketRateLimiter rateLimiter);
+
+    // private double _tokenCount;
+    [UnsafeAccessor(UnsafeAccessorKind.Field, Name = "_tokenCount")]
+    private static extern ref double PrivateGetTokenCount(TokenBucketRateLimiter rateLimiter);
+}