[Enhancement] Add loading animation for switching workspaces

[gadfly3173]

When switching workspaces, the UI will get stuck. Even if you minimize the window, the context menu will remain on the screen until the workspace switch is complete. It seems that opening the repository is a time-consuming operation. I hope to add a loading animation to the function of switching workspaces.

[SwitchWorkspace] Starting workspace switch to: xxxx
[SwitchWorkspace] Task check completed: 3ms
[SwitchWorkspace] Workspace states updated: 6ms
[SwitchWorkspace] Existing pages cleared: 111ms
[SwitchWorkspace] 5 repositories reopened: 1164ms
[SwitchWorkspace] Active page set: 1169ms
[SwitchWorkspace] Preferences saved: 1177ms
[SwitchWorkspace] Completed in 1205ms

[love-linger]

It's because we need get the $GIT_DIR before opening a repository.

These two commands took up most of the time. You can test it by the following code

- gitdir = new Commands.QueryGitDir(node.Id).Result();
+ gitdir = Path.Combine(node.Id, ".git");

[love-linger]

I'm not sure if the follow code is a right way to solve this problem:

[gadfly3173]

I'm not sure if the follow code is a right way to solve this problem:

[SwitchWorkspace] Task check completed: 6ms
[SwitchWorkspace] Workspace states updated: 10ms
[SwitchWorkspace] Existing pages cleared: 103ms
[SwitchWorkspace] 5 repositories reopened: 1329ms
[SwitchWorkspace] Active page set: 1333ms
[SwitchWorkspace] Preferences saved: 1336ms
[SwitchWorkspace] Completed in 1379ms

Doesn't seem to be better.

BTW, I noticed that switching workspaces when the repository is not fully loaded may cause some AggregateExceptions, probably because the repository is closed during the execution of some Task.Run.

System.AggregateException: A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the finalizer thread. (Object reference not set to an instance of an object.)
 ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at SourceGit.ViewModels.Repository.BuildBranchTree(List`1 branches, List`1 remotes) in /home/xxx/Documents/sourcegit/src/ViewModels/Repository.cs:line 2282
   at SourceGit.ViewModels.Repository.RefreshBranches() in /home/xxx/Documents/sourcegit/src/ViewModels/Repository.cs:line 915
   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread)
   --- End of inner exception stack trace ---

[gadfly3173]

[OpenRepositoryInTab] Starting to open: A JAVA PROJECT
[OpenRepositoryInTab] Existing tab check completed: 32ms
[OpenRepositoryInTab] Bare repository check completed: 36ms
[OpenRepositoryInTab] Git directory resolved: 41ms
[OpenRepositoryInTab] Repository opened: 95ms
[OpenRepositoryInTab] Page setup completed: 116ms
[OpenRepositoryInTab] Workspace state updated: 139ms
[OpenRepositoryInTab] Completed in 142ms
[OpenRepositoryInTab] Starting to open: AN ANGULAR PROJECT
[OpenRepositoryInTab] Existing tab check completed: 21ms
[OpenRepositoryInTab] Bare repository check completed: 43ms
[OpenRepositoryInTab] Git directory resolved: 64ms
[OpenRepositoryInTab] Repository opened: 455ms
[OpenRepositoryInTab] Page setup completed: 459ms
[OpenRepositoryInTab] Workspace state updated: 462ms
[OpenRepositoryInTab] Completed in 465ms



[Repository.Open] Settings loaded: 3ms
[Repository.Open] Watcher initialized: 394ms
[Repository.Open] View components initialized: 433ms
[Repository.Open] Auto-fetch timer started: 447ms
[Repository.Open] Started refresh tasks: 454ms
[Repository.Open] Repository opened in 458ms

It seems that repository with node_modules would run slower in repo.Open()

[love-linger]

Repository.Open 从代码上看，只有以下两个可能耗时的地方

1. 加载并解析 <repo>/.git/sourcegit.settings 文件
2. 当其 $GIT_DIR 包含 /worktrees/ 时，创建 git rev-parse --git-common-dir 进程读取 $GIT_COMMON_DIR

其他的耗时操作都在异步线程中。

在我的测试中，如果没有IO输出，基本上大部分的耗时都在 git 命令调用上。

[gadfly3173]

[Repository.Open] Settings loaded: 3ms
[Repository.Open] GitDir for watcher resolved:  9ms
[Repository.Open] Watcher initialized: 439ms
[Repository.Open] View components initialized: 445ms
[Repository.Open] Auto-fetch timer started: 448ms
[Repository.Open] Started refresh tasks: 453ms
[Repository.Open] Repository opened in 457ms

我这里看下来应该完全就是Watcher非常耗时。看起来watcher是在设置Path的时候就会直接启动。考虑到这是完全用于后台的文件监听，这可能也是可以用Task.Run来初始化的？

[love-linger]

我的电脑配置按理说配置很高：AMD 7950X，仓库在固态硬盘中。测试结果与你的很不一样：

Query $GIT_DIR for $E:/Mine/sourcegit cost 27ms
Create watcher for $E:/Mine/sourcegit cost $0ms
Query $GIT_DIR for $E:/Github/Avalonia cost 47ms
Create watcher for $E:/Github/Avalonia cost $0ms
Query $GIT_DIR for $E:/Github/AvaloniaEdit cost 49ms
Create watcher for $E:/Github/AvaloniaEdit cost $0ms
Query $GIT_DIR for $E:/Github/STL cost 55ms
Create watcher for $E:/Github/STL cost $0ms
Query $GIT_DIR for $E:/Github/github-star-stats cost 54ms
Create watcher for $E:/Github/github-star-stats cost $0ms
Query $GIT_DIR for $E:/Github/TextMateSharp cost 55ms
Create watcher for $E:/Github/TextMateSharp cost $0ms
Query $GIT_DIR for $E:/Next/UnrealEngine cost 35ms
Create watcher for $E:/Next/UnrealEngine cost $0ms
Exception thrown: 'System.AggregateException' in System.Private.CoreLib.dll
Query $GIT_DIR for $E:/Mine/sourcegit cost 26ms
Create watcher for $E:/Mine/sourcegit cost $0ms
Query $GIT_DIR for $E:/Github/Avalonia cost 40ms
Create watcher for $E:/Github/Avalonia cost $0ms
Query $GIT_DIR for $E:/Github/AvaloniaEdit cost 46ms
Create watcher for $E:/Github/AvaloniaEdit cost $0ms
Exception thrown: 'System.AggregateException' in System.Private.CoreLib.dll
Query $GIT_DIR for $E:/Github/STL cost 53ms
Create watcher for $E:/Github/STL cost $0ms
Query $GIT_DIR for $E:/Github/github-star-stats cost 62ms
Create watcher for $E:/Github/github-star-stats cost $0ms
Query $GIT_DIR for $E:/Github/TextMateSharp cost 54ms
Create watcher for $E:/Github/TextMateSharp cost $0ms
Query $GIT_DIR for $E:/Next/UnrealEngine cost 57ms
Create watcher for $E:/Next/UnrealEngine cost $0ms

[love-linger]

你在测试watcher前，restart一下StopWatch呢

[love-linger]

这是我测试的代码

• Repository.cs

                var sw = new System.Diagnostics.Stopwatch();
                sw.Start();
                _watcher = new Models.Watcher(this, _fullpath, gitDirForWatcher);
                System.Diagnostics.Debug.WriteLine($"Create watcher for ${_fullpath} cost ${sw.ElapsedMilliseconds}ms");

• Launcher.cs

var sw = new System.Diagnostics.Stopwatch();
sw.Start();
var isBare = new Commands.IsBareRepository(node.Id).Result();
var gitDir = node.Id;
if (!isBare)
{
    gitDir = new Commands.QueryGitDir(node.Id).Result();
    if (string.IsNullOrEmpty(gitDir))
    {
        var ctx = page == null ? ActivePage.Node.Id : page.Node.Id;
        App.RaiseException(ctx, "Given path is not a valid git repository!");
        return;
    }
}
System.Diagnostics.Debug.WriteLine($"Query $GIT_DIR for ${node.Id} cost {sw.ElapsedMilliseconds}ms");

[gadfly3173]

设备:                  Gigabyte Technology Co., Ltd. B250M-D3H (Default string) Desktop Computer 
操作系统:                Deepin 23 Community Linux version 6.12.9-amd64-desktop-rolling (root@deepinci-amd7) (gcc (Deepin 12.3.0-17deepin8) 12.3.0, GNU ld (GNU Binutils for Deepin) 2.41) #23.01.01.18 SMP PREEMPT_DYNAMIC Fri Jan 10 18:29:31 CST 2025
处理器:                 Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz (四核 / 四逻辑处理器)
主板:                  B250M-D3H-CF
内存:                  16GB(KF3200C16D4/16GX DDR4 2400 MT/s)/8GB(KHX2400C15/8G DDR4 2400 MT/s)/8GB(KHX2400C15D4/8G DDR4 2400 MT/s)
存储设备:                KINGSTON SA400S37240G (240 GB)

我这台Linux设备配置比较差，我的Windows机器配置也比较高，不会遇到这种问题。

[love-linger]

这样看上去有以下几个可能：

• .NET 实现的Linux平台的FileSystemWatcher存在性能问题
• Linux平台本身的文件系统对于FileSystemWatcher兼容上的性能问题

[gadfly3173]

看起来就是dotnet对Linux的FileWatcher实现是比较耗时的那一类。

https://github.com/dotnet/runtime/blob/669df89081734ba2ed8cb499673c2ba1d9a72442/src/libraries/System.IO.FileSystem.Watcher/src/System/IO/FileSystemWatcher.Linux.cs#L274-L296

在启动监听之前会递归添加所有目录。。。Win32的实现就是只需要创建一个文件夹句柄