Powershell 一次将 BITS 传输限制为 4

Question

我正在编写一个脚本，使用 BITS 将 Office 365 ProPlus 二进制文件传输到 12 个单独的文件共享。我还想在屏幕上显示这些传输的进度。我的问题是，我想将同时传输的 BITS 数量限制在一次不超过 4 个。当一项工作完成后，我想开始队列中的下一项工作并继续接收进度，直到所有工作完成。

这就是我目前所拥有的。我首先使用此函数为处于暂停状态的所有网络位置创建我的所有 BITS 作业。

function Start-BinaryTransfer
{
[CmdletBinding()]
param
(
    [array]$DistrictsToUpdate
)

$Source = "$BaseSource$UpdateChannel"

if ("All" -in $DistrictsToUpdate.Split(','))
{
    foreach ($Destination in $ReposList)
    {
        Copy-Item -Path $Source -Destination $($Destination.Location + '\') -Filter { $_.PSisContainer } -Recurse -ErrorAction SilentlyContinue
        Get-ChildItem -Path $Source -Recurse | Where-Object{ $_.PSisContainer } | ForEach-Object {
            $spath = $_.FullName.Remove(0, $Source.Length + 1)
            $BITSJobs += Start-BitsTransfer -Source $Source$spath\*.* `
                                            -Destination "$($Destination.Location)$UpdateChannel$spath" `
                                            -DisplayName "$($Destination.District) File Transfer" `
                                            -Description "Transferring from [$Source] to [$($Destination.Location)$UpdateChannel]" `
                                            -Suspended
        }
    }
}

创建完所有作业后，我尝试使用此 While 循环一次启动 4 个作业，并显示进度。不幸的是，实际行为是它会尝试同时启动所有 12 个作业，这会导致网络资源陷入困境。

While (Get-BitsTransfer | Where JobState -EQ "Suspended")
{
Get-BitsTransfer | Where JobState -EQ "Suspended" | ForEach-Object {
    for ($JobsCount = 0; $JobsCount -le 4; $JobsCount++)
    {
        if ($JobsCount -lt 4)
        {
            Resume-BitsTransfer -BitsJob $_ -Asynchronous
            Get-BitsTransfer | Where JobState -EQ "Transferring" | ForEach-Object {
                Write-Progress `
                               -Id $([math]::Abs($_.DisplayName.GetHashCode())) `
                               -Activity "$($_.DisplayName)" `
                               -Status "$($_.Description)" `
                               -CurrentOperation "$([math]::Floor($_.BytesTransferred / $_.BytesTotal * 100)) % Complete" `
                               -PercentComplete $([math]::Floor($_.BytesTransferred / $_.BytesTotal * 100))
            }
        }
      }
    }

    if (Get-BitsTransfer | Where JobState -EQ "Transferred")
    {
        Get-BitsTransfer | Where JobState -EQ "Transferred" | Complete- BitsTransfer
        $JobsCount--
    }
}

Answer 1

使用 for 循环，您将每隔运行

将 $JobsCount 重置为 0

for ($JobsCount = 0; $JobsCount -le 4; $JobsCount++)

像这样的东西应该可以工作（对当前代码进行最少的更改）：

$JobsCount = 0
While (Get-BitsTransfer | Where JobState -EQ "Suspended")
{
Get-BitsTransfer | Where JobState -EQ "Suspended" | ForEach-Object {
    # remove for-loop
        if ($JobsCount -lt 4)
        {
            $JobsCount++
            ...

您还必须修改您的 while-loop，目前它会在 JobState "Suspended" 没有更多工作时退出，但您仍然需要等待工作使用 JobState "Transferring" 并在 "Transferred" 时完成它们。建议：While ((Get-BitsTransfer) -ne $null)或者更简单的While (Get-BitsTransfer)

Answer 2

感谢您的建议，成功了。我计划进一步完善我的代码，但这是我目前可用的代码。

function Update-JobProgress
{
    [CmdletBinding()]
    param ()

    Get-BitsTransfer | Where-Object { ($_.JobState -EQ "Transferring") -and ($_.DisplayName -Like "*File Transfer") } | ForEach-Object {
        Write-Progress -Id $([math]::Abs($_.DisplayName.GetHashCode())) `
                       -Activity "$($_.DisplayName)" `
                       -Status "$($_.Description)" `
                       -CurrentOperation "$([math]::Floor($_.BytesTransferred / $_.BytesTotal * 100)) % Complete" `
                       #-PercentComplete $([math]::Floor($_.BytesTransferred / $_.BytesTotal * 100))
    }
}


While (Get-BitsTransfer)
{
    $JobsCount = (Get-BitsTransfer | Where-Object { ($_.JobState -ne "Suspended") -and ($_.DisplayName -Like "*File Transfer") }).Count

    Get-BitsTransfer | Where-Object JobState -EQ "Suspended" | ForEach-Object {
        if ($JobsCount -lt 4)
        {
            Resume-BitsTransfer -BitsJob $_ -Asynchronous
            $JobsCount++
        }
    }

    Update-JobProgress

    if (Get-BitsTransfer | Where-Object { ($_.JobState -EQ "Transferred") -and ($_.DisplayName -Like "*File Transfer") })
    {
        Get-BitsTransfer | Where-Object { ($_.JobState -EQ "Transferred") -and ($_.DisplayName -Like "*File Transfer") } | ForEach-Object {
            Write-Progress `
                           -Id $([math]::Abs($_.DisplayName.GetHashCode())) `
                           -Activity "$($_.DisplayName)" `
                           -Completed
            $_ | Complete-BitsTransfer
            $JobsCount--
        }
    }
}

在我的测试中，我发现使用 -PercentComplete 开关在控制台中实际显示滚动进度条的结果不一致 window；完成的第一份工作往往会拖延并导致奇怪的视觉故障。省略开关并放弃进度条似乎可以解决问题。

Powershell 一次将 BITS 传输限制为 4

Powershell limiting BITS transfers to 4 at a time

powershell

loops

microsoft-bits

progress-bar