结论：别用这个函数，他会把内存写不下的写到硬盘的虚拟内存中去（注：硬盘中的虚拟内存默认在系统盘里）
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[System.Runtime.InteropServices.DllImportAttribute("kernel32.dll", EntryPoint = "SetProcessWorkingSetSize", ExactSpelling = true, CharSet =System.Runtime.InteropServices.CharSet.Ansi, SetLastError = true)]
private static extern int SetProcessWorkingSetSize(IntPtr process, int minimumWorkingSetSize, int maximumWorkingSetSize);
public void Dispose(){
GC.Collect();
GC.SuppressFinalize(this);
if (Environment.OSVersion.Platform == PlatformID.Win32NT)
{
SetProcessWorkingSetSize(System.Diagnostics.Process.GetCurrentProcess().Handle, -1, -1);
}}