Getting Computer Memory Usage

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Here’s a quick spot-check on the memory usage on remote computer (or a few dozen computers).  It uses WMI objects – Win32_ComputerSystem for the TotalPhysicalMemory and Win32_OperatingSystem for FreePhysicalMemory, TotalVirtualMemorySize (why did they add a 'size' here?), and FreeVirtualMemory.

 

Along the way, it does some formatting and conversions so everything uses the same units, and calculates the percentage of memory used. Very simple, but useful for things like when someone asks how many machines in the lab have less than 8GB of RAM

 

 

function Get-ComputerMemory {
     param (
         [Parameter( 
             Position = 0,  
             ValueFromPipeline = $true, 
             ValueFromPipelineByPropertyName = $true 
         )] [String[]]$ComputerName = @($env:COMPUTERNAME.ToLower()),
         [int]$digits = 3
     );
     process {
         foreach ($computer in $ComputerName ) {
             $object = 1 | Select-Object ComputerName, TotalPhysicalMemoryGB, FreePhysicalMemoryGB, UsedPhysicalMemory, TotalVirtualMemoryGB, FreeVirtualMemoryGB, UsedVirtualMemory;
            
             Write-Progress "Get-WmiObject Win32_ComputerSystem" "-ComputerName $computer"
             $wmiCompSys = Get-WmiObject Win32_ComputerSystem -ComputerName $computer;
             if (!$wmiCompSys) { 
                 Write-Warning "Unable to get Win32_ComputerSystem data from $computer"; 
             }

             Write-Progress "Get-WmiObject Win32_OperatingSystem" "-ComputerName $computer"
             $wmiOpSys = Get-WmiObject Win32_OperatingSystem -ComputerName $computer;
             if (!$wmiOpSys) {
                 Write-Warning "Unable to get Win32_OperatingSystem data from $computer";
             }
            
             $object.ComputerName = $computer.ToLower();
            
             # normalize to GB. NOTE: Win32_OperatingSystem returns KB while Win32_ComputerSystem returns bytes.
             $totalPhys = $wmiCompSys.TotalPhysicalMemory / 1GB;
             $freePhys = $wmiOpSys.FreePhysicalMemory / 1MB;
             $totalVirt = $wmiOpSys.TotalVirtualMemorySize / 1MB;
             $freeVirt = $wmiOpSys.FreeVirtualMemory / 1MB
            
             $object.TotalPhysicalMemoryGB = ("{0:N$digits}" -f ($totalPhys + .5)) -as [float];
             $object.FreePhysicalMemoryGB = ("{0:N$digits}" -f ($freePhys + .5)) -as [float];
             $object.UsedPhysicalMemory = [int]((100 * (1 - ($freePhys/$totalPhys))) + .5);

            
             $object.TotalVirtualMemoryGB = ("{0:N$digits}" -f ($totalVirt + .5)) -as [float];
             $object.FreeVirtualMemoryGB = ("{0:N$digits}" -f  ($freeVirt + .5)) -as [float];
             $object.UsedVirtualMemory = [int]((100 * (1 - ($freeVirt/$totalVirt))) + .5);
            
             $object;
         }
     }
}