Ya, laptop lama saya beberapa kali lebih kuat daripada server produksi Anda

set nocount on
create table _t (v varchar(100))
declare @n int=300000
while @n>0 begin 
  insert into _t select 'What a slowpoke!'
  delete from _t
  set @n=@n-1
  end
GO
drop table _t

(dalam komentar ternyata saya berbohong - saya telah menunda daya tahan di kedua tempat. Tanpa daya tahan yang tertunda ternyata:
Desktop - 39 detik, 15K tr / detik, bolak-balik 0,065ms / io
PROD PROD - 360 detik, 1600 tr / detik, 0,6 ms
saya seharusnya memperhatikan terlalu cepat)

create function dbo.isPrime (@n bigint)
returns int
as
  begin
  if @n = 1 return 0
  if @n = 2 return 1
  if @n = 3 return 1
  if @n % 2 = 0 return 0
  declare @sq int
  set @sq = sqrt(@n)+1 -- check odds up to sqrt
  declare @dv int = 1
  while @dv < @sq 
    begin
	set @dv=@dv+2
	if @n % @dv = 0 return 0
	end
  return 1
  end
GO
declare @dt datetime set @dt=getdate()
select dbo.isPrime(1000000000000037)
select datediff(ms,@dt,getdate()) as ms
GO

    class Program
    {
        [DllImport("kernel32.dll")]
        static extern void GetSystemTimePreciseAsFileTime(out FILE_TIME lpSystemTimeAsFileTime);

        [StructLayout(LayoutKind.Sequential)]
        struct FILE_TIME
        {
            public int ftTimeLow;
            public int ftTimeHigh;
        }

        static void Main(string[] args)
        {
            for (int i = 0; i < 16; i++)
            {
                int counter = 0;

                var stopwatch = Stopwatch.StartNew();

                while (stopwatch.ElapsedMilliseconds < 1000)
                {
                    GetSystemTimePreciseAsFileTime(out var fileTime);
                    counter++;
                }

                if (i > 0)
                {
                    Console.WriteLine("{0}", counter);
                }
            }
        }
    }

• Ini biasanya tidak menakutkan. Tetapi: ketika pindah dari host 'asli' ke host dengan frekuensi 'berbeda', VMware harus menyesuaikan hasil GetTimePrecise.
• Sebagai aturan, ini tidak menakutkan, kecuali ada aplikasi yang meminta waktu yang tepat jutaan kali per detik, seperti server SQL.
• Tapi ini tidak menakutkan, karena SQL server tidak selalu melakukan ini (lihat Kesimpulannya)

Keputusan

When you disable virtualization of the TSC, reading the TSC from within the virtual machine returns the physical machine’s TSC value, and writing the TSC from within the virtual machine has no effect. Migrating the virtual machine to another host, resuming it from suspended state, or reverting to a snapshot causes the TSC to jump discontinuously. Some guest operating systems fail to boot, or exhibit other timekeeping problems, when TSC virtualization is disabled. In the past, this feature has sometimes been recommended to improve performance of applications that read the TSC frequently, but performance of the virtual TSC has been improved substantially in current products. The feature has also been recommended for use when performing measurements that require a precise source of real time in the virtual machine.

Kesimpulan