mkdir仍然是原子的吗？ (安装在SAN上的Windows 7文件系统)

使用PowerShell创建共享文件夹以用作互斥锁时,我也得到了令人困惑的结果,所以我创建了一个测试脚本.

function New-FolderMutex {
    try {
        New-Item -ItemType directory -Path .TheMutex -ErrorAction Stop > $null
        $true
    } catch {
        $false
    }
}

function Remove-FolderMutex {
    Remove-Item -Path .TheMutex
}

1..100 | % {
    if (New-FolderMutex) {
        Write-Host "Inside loop $_"
        Remove-FolderMutex
    }
}

当前目录位于网络共享中时,将运行此脚本.

当我在两个单独的PowerShell控制台中同时运行此脚本时,从错误消息中可以清楚地看出该方法注定失败了.调用Remove-Item会产生许多不同的错误,即使它只是由创建该文件夹的进程调用.在幕后似乎发生了一大堆非原子步骤.

当然,OP询问mkdir(可能是系统调用),我的例子使用更高级别的PowerShell cmdlet,但我希望这有一些兴趣.

两个进程之一的示例输出(为简洁起见编辑)

Inside loop 30
Inside loop 31
Inside loop 32
Inside loop 33
Inside loop 34
Remove-Item : Access to the path 'H:My DocumentsPowerShellMutexFolderTheMutex' is denied.
At H:My DocumentsPowerShellMutexFolderTest-FolderMutex.ps1:93 char:5
+     Remove-Item -Path .TheMutex
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : PermissionDenied: (H:My Documents...FolderTheMutex:String) [Remove-Item],UnauthorizedAccessException
    + FullyQualifiedErrorId : RemoveItemUnauthorizedAccessError,Microsoft.PowerShell.Commands.RemoveItemCommand

Inside loop 39
Remove-Item : H:My DocumentsPowerShellMutexFolderTheMutex is a NTFS junction point. Use the Force parameter to delete or modify.
At H:My DocumentsPowerShellMutexFolderTest-FolderMutex.ps1:93 char:5
+     Remove-Item -Path .TheMutex
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : WriteError: (H:My Documents...FolderTheMutex:DirectoryInfo) [Remove-Item],IOException
    + FullyQualifiedErrorId : DirectoryNotEmpty,Microsoft.PowerShell.Commands.RemoveItemCommand

Inside loop 42
Remove-Item : Could not find a part of the path 'H:My DocumentsPowerShellMutexFolderTheMutex'.
At H:My DocumentsPowerShellMutexFolderTest-FolderMutex.ps1:93 char:5
+     Remove-Item -Path .TheMutex
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : WriteError: (H:My Documents...FolderTheMutex:String) [Remove-Item],DirectoryNotFoundException
    + FullyQualifiedErrorId : RemoveItemIOError,Microsoft.PowerShell.Commands.RemoveItemCommand

Inside loop 44
Inside loop 45