Determine physical CPU count for a computer using C#

It appears that this is a C# client applications that calls a C++ coded compiled DLL. In this case, it would be C++ that is determining the CPU counts. Do you how this might convert to C# or another way?  I would rather not reference any external DLLs and only use the built -in .NET framework.

Thanks!

I'll be honest, you got me intrigued, so I have been doing some googling since I posted this. This is the best sample I could find that uses C#. The C++ is managed C++, so is native .NET anyway, but I suspect that this is not properly exposed in .NET.

It is also possible that the sample in that article does not accurately count the cores, but I don't have a DC machine with me right now to test it.

If I find more, I will post here.

You can use

            ManagementClass mc = new ManagementClass("Win32_Processor");
            ManagementObjectCollection moc = mc.GetInstances();

to get the WMI information on the processors.


Have a look in the System.Management documnetation.

Thanks ostdp,
However, that returns the logical, not the physical processor count. I am very familiar on the WMI object model, however, it appears that you cannot return the physical count, only the logical count. If there is a way to convert that C++ code to C#, that would defnitely suffice.

Thanks

Expert1701 ,
It appears that this code only reads the ProcessorID using WMI and counts all the unique instances. However, on a PowerEdge 6650, Xeon, Quad Proc server, this only returned 1 processor. When looking over the Processor ID in WMI (Win32_Processor), I can find 8 instances of processors, all of them have the same ProcessorID. This is why when I ran the utility, it only returned 1 processor.

It also appears that if I were to use the C++ compiled dll, I would not be able to check the CPU count remotely, as it does not have an interface for that. I need to be able to connect to hundreds of servers and remotely determine the physical CPU count.

I hope that helps.

Thanks!

Can you examine the other properties for something that is unique?

That is the problem. I have looked at all of the Win32_Processor WMI properties and not found anything that is unique to physical processors. I am looking for any other possibilities.

Thanks!

What operating system is that PowerEdge 6650 running?

Windows 2003 SP1

OK, Thanks everyone. I finally got this working. In the spirit of sharing, this is what I have. So far, it appears to work. I will be running a test tonight against all servers and comparing that data with the purchase orders (they are on paper and they specify the real processor count, I wanted something automated though...)

I found that the SocketDesignation property from the Win32_Processor class has which physical socket the CPU is located in. If there are more than one logical CPUs using a single socket, I can ignore that duplicate (it is a virtual CPU). I used the same code that Expert1701 provided exchanging ProcessorID with SocketDesignation.

I will keep the Q open until tomorrow until I can verify this works on all servers. If this does work, i will award the points to Expert1702

Thanks everyone!


--------- Begin code snippet here -------------------------------------------------------
using System;
  using System.Collections;
  using System.Management;
  using System.Runtime.InteropServices;

  class Program
  {
    static void Main()
    {
      Console.WriteLine("Logical CPUs:  " + Environment.ProcessorCount);
      Console.WriteLine("Physical CPUs: " + PhysicalProcessorCount());
      Console.ReadLine();
    }

    static int PhysicalProcessorCount()
    {
      ArrayList processors = new ArrayList();

      foreach (ManagementObject mo in new ManagementClass("Win32_Processor").GetInstances())
      {
        string id = (string)mo.Properties["SocketDesignation"].Value;

        if (!processors.Contains(id))
          processors.Add(id);
      }

      return processors.Count;
    }
  }
--------- End code snippet here -------------------------------------------------------

I tested and verified this. this works as planned.

Thank you everyone!

Just out of curiosity, what types of values does SocketDesignation have on a multi-processor system?

Here is a sample:
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_1
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_2
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_3
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_4
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_1
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_1
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_1
-----------------------------------
Win32_Processor instance
-----------------------------------
SocketDesignation: PROC_1

FYI - That shows 8 logical instances but only 4 unique socket designations. This means that out of the 8 logical processors in the system, they are only using 4 physical sockets. That means that 4 processors are physically installed.