param(
    [Parameter(Mandatory=$true)]
    [string]$name,
    [Parameter(Mandatory=$true)]
    [long]$size
)

$random = new-object Random
$linePerMB = 1024
$dataPerLine = 256
$lines = @("") * $linePerMB
$data = @(0) * $dataPerLine

for($mb = 1; $mb -le $size / 1MB; $mb++) {
    for($line = 0; $line -lt $linePerMB; $line++) {
        for($i = 0; $i -lt $dataPerLine; $i++) {
            $data[$i] = $random.Next(100, 1000)
        }

        $lines[$line] = [string]::Join(',', $data)
    }

    [string]::Join("`n", $lines) | out-file $name -encoding utf8 -append
    write-host "${mb}MB done"
}