fix #291

cache file system 新增参数：最大并发数和每帧请求最大数
2024-12-17 17:14:59 +08:00
parent 8c532798cb
commit 985c76d8ce
4 changed files with 177 additions and 65 deletions
@@ -0,0 +1,139 @@
+using System;
+using System.Collections.Generic;
+
+namespace YooAsset
+{
+    internal class DefaultCacheDownloadCenter
+    {
+        private readonly DefaultCacheFileSystem _fileSystem;
+        protected readonly Dictionary<string, DefaultDownloadFileOperation> _downloaders = new Dictionary<string, DefaultDownloadFileOperation>(1000);
+        protected readonly List<string> _removeDownloadList = new List<string>(1000);
+
+        public DefaultCacheDownloadCenter(DefaultCacheFileSystem fileSystem)
+        {
+            _fileSystem = fileSystem;
+        }
+
+        /// <summary>
+        /// 更新下载中心
+        /// </summary>
+        public void Update()
+        {
+            // 获取可移除的下载器集合
+            _removeDownloadList.Clear();
+            foreach (var valuePair in _downloaders)
+            {
+                var downloader = valuePair.Value;
+
+                // 注意：主动终止引用计数为零的下载任务
+                if (downloader.RefCount <= 0)
+                {
+                    _removeDownloadList.Add(valuePair.Key);
+                    downloader.SetAbort();
+                    continue;
+                }
+
+                if (downloader.IsDone)
+                {
+                    _removeDownloadList.Add(valuePair.Key);
+                    continue;
+                }
+            }
+
+            // 移除下载器
+            foreach (var key in _removeDownloadList)
+            {
+                _downloaders.Remove(key);
+            }
+
+            // 最大并发数检测
+            int processCount = GetProcessingOperationCount();
+            if (processCount != _downloaders.Count)
+            {
+                if (processCount < _fileSystem.DownloadMaxConcurrency)
+                {
+                    int startCount = _fileSystem.DownloadMaxConcurrency - processCount;
+                    if (startCount > _fileSystem.DownloadMaxRequestPerFrame)
+                        startCount = _fileSystem.DownloadMaxRequestPerFrame;
+
+                    foreach (var operationPair in _downloaders)
+                    {
+                        var operation = operationPair.Value;
+                        if (operation.Status == EOperationStatus.None)
+                        {
+                            OperationSystem.StartOperation(_fileSystem.PackageName, operation);
+                            startCount--;
+                            if (startCount <= 0)
+                                break;
+                        }
+                    }
+                }
+            }
+        }
+
+        /// <summary>
+        /// 创建下载任务
+        /// </summary>
+        public FSDownloadFileOperation DownloadFileAsync(PackageBundle bundle, DownloadParam param)
+        {
+            // 查询旧的下载器
+            if (_downloaders.TryGetValue(bundle.BundleGUID, out var oldDownloader))
+            {
+                oldDownloader.Reference();
+                return oldDownloader;
+            }
+
+            // 设置请求URL
+            bool importFile = false;
+            if (string.IsNullOrEmpty(param.ImportFilePath))
+            {
+                param.MainURL = _fileSystem.RemoteServices.GetRemoteMainURL(bundle.FileName);
+                param.FallbackURL = _fileSystem.RemoteServices.GetRemoteFallbackURL(bundle.FileName);
+            }
+            else
+            {
+                // 注意：把本地文件路径指定为远端下载地址
+                param.MainURL = DownloadSystemHelper.ConvertToWWWPath(param.ImportFilePath);
+                param.FallbackURL = param.MainURL;
+                importFile = true;
+            }
+
+            // 创建新的下载器
+            DefaultDownloadFileOperation newDownloader;
+            if (bundle.FileSize >= _fileSystem.ResumeDownloadMinimumSize)
+            {
+                newDownloader = new DownloadResumeFileOperation(_fileSystem, _fileSystem, bundle, param, _fileSystem.ResumeDownloadResponseCodes);
+                newDownloader.Reference();
+                _downloaders.Add(bundle.BundleGUID, newDownloader);
+            }
+            else
+            {
+                newDownloader = new DownloadNormalFileOperation(_fileSystem, _fileSystem, bundle, param);
+                newDownloader.Reference();
+                _downloaders.Add(bundle.BundleGUID, newDownloader);
+            }
+
+            // 注意：导入文件不要限制并发！导入文件涉及到异步转同步，限制并发会导致主线程卡死风险！
+            if (importFile)
+            {
+                OperationSystem.StartOperation(_fileSystem.PackageName, newDownloader);
+            }
+            return newDownloader;
+        }
+
+        /// <summary>
+        /// 获取正在进行中的下载器总数
+        /// </summary>
+        private int GetProcessingOperationCount()
+        {
+            int count = 0;
+            foreach (var operationPair in _downloaders)
+            {
+                var operation = operationPair.Value;
+                if (operation.Status != EOperationStatus.None)
+                    count++;
+            }
+            return count;
+        }
+    }
+}