dsccommunity / ComputerManagementDsc

DSC resources for for configuration of a Windows computer. These DSC resources allow you to perform computer management tasks, such as renaming the computer, joining a domain and scheduling tasks as well as configuring items such as virtual memory, event logs, time zones and power settings.
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VirtualMemory: 'value out of range' error when sizes > 1/8th of the disk #376

Open KenBenjamin opened 3 years ago

KenBenjamin commented 3 years ago

Details of the scenario you tried and the problem that is occurring

I'm trying to utilize Azure VM temp disks for the pagefile but due to their small size (typically 2x RAM) and a limitation in Set-CimInstance (and similar methods), it's not possible to create anything of much use (e.g. only 1Gb on an 8Gb temp drive).

For example, splitting out the offending command in Set-PageFileSetting against an 8Gb drive with sufficient free space:

    $Drive = 'D:'
    $InitialSize = 4096
    $MaximumSize = 7000

    $setParams = @{
        Namespace = 'root\cimv2'
        Query     = "Select * from Win32_PageFileSetting where SettingID='pagefile.sys @ $Drive'"
        Property  = @{
            InitialSize = $InitialSize
            MaximumSize = $MaximumSize
        }
    }

    Set-CimInstance @setParams

Throws the following error:

Verbose logs showing the problem

Set-CimInstance : Value out of range 
At line:1 char:5
+     Set-CimInstance @setParams
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (Win32_PageFileS...\pagefile.sys"):CimInstance) [Set-CimInstance], CimException
    + FullyQualifiedErrorId : HRESULT 0x8004102b,Microsoft.Management.Infrastructure.CimCmdlets.SetCimInstanceCommand

Suggested solution to the issue

All the CIM-based solutions seem to have a base class that is the underlying issue. To work around it, the only solution I've found is to directly set the registry key:

<#
    .SYNOPSIS
        Sets a new page file name.
    .PARAMETER Drive
        The letter of the drive containing the page file
        to change the settings of.
    .PARAMETER InitialSize
        The initial size to set the page file to.
    .PARAMETER MaximumSize
        The maximum size to set the page file to.
#>
function Set-PageFileSetting
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [System.String]
        $Drive,

        [Parameter()]
        [System.Int64]
        $InitialSize = 0,

        [Parameter()]
        [System.Int64]
        $MaximumSize = 0
    )
        # Using Set-CimInstance fails if pagefile exceeds 1/8th of the available disk space so we're switching to using direct registry key settings.
        $pageFileName = Join-Path `
                    -Path $driveInfo.Name `
                    -ChildPath 'pagefile.sys'

        $value = "$pageFileName $InitialSize $MaximumSize`n" # Even though it's a Reg_SZ_Multi, it's not double-null terminated
        # TODO: Fix to support other drive values

        Set-ItemProperty `
            -LiteralPath 'HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management' `
            -Name 'PagingFiles' `
            -Type MultiString `
            -Value $value `
            -Force
    }

   Write-Verbose -Message ($script:localizedData.SettingPageFileSettingsMessage -f $Drive, $InitialSize, $MaximumSize)
}

The above is incomplete as it does not account for any other / pre-existing settings on another drive but that shouldn't be too hard to work out given the simple data structure of the registry key.

The DSC configuration that is used to reproduce the issue (as detailed as possible)

Using a system with a D: drive that is 8Gb in size:

    VirtualMemory "pagefile"
    {
      Type        = 'CustomSize'
      Drive       = 'D'
      InitialSize = 4096
      MaximumSize = 7000
    }

The operating system the target node is running

OsName               : Microsoft Windows Server 2019 Datacenter
OsOperatingSystemSKU : DatacenterServerEdition
OsArchitecture       : 64-bit
WindowsVersion       : 1809
WindowsBuildLabEx    : 17763.1.amd64fre.rs5_release.180914-1434
OsLanguage           : en-US
OsMuiLanguages       : {en-US}

Version and build of PowerShell the target node is running

Name                           Value                                                                                                                                                               
----                           -----                                                                                                                                                               
PSVersion                      5.1.17763.1971                                                                                                                                                      
PSEdition                      Desktop                                                                                                                                                             
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}                                                                                                                                             
BuildVersion                   10.0.17763.1971                                                                                                                                                     
CLRVersion                     4.0.30319.42000                                                                                                                                                     
WSManStackVersion              3.0                                                                                                                                                                 
PSRemotingProtocolVersion      2.3                                                                                                                                                                 
SerializationVersion           1.1.0.1                                                                                                                                                             

Version of the DSC module that was used ('dev' if using current dev branch)

8.4.0