Exception: Instance 'Name of instance' does not exist in the specified Category

Question

When I create and use performance counters like this:

private readonly PerformanceCounter _cpuPerformanceCounter;
public ProcessViewModel(Process process)
           


        

Answer 1

Here is my solution for all processes and multiple process instances:

var processes = Process.GetProcesses().GroupBy(g => g.ProcessName);
        List> pcList = new List>();
        foreach (var pg in processes)
        {
            if (pg.First().ProcessName == "Idle")
                continue;

            if (pg.Count() == 1)
            {
                var process_cpu = new PerformanceCounter(
                           "Process",
                           "% Processor Time",
                           pg.First().ProcessName
                                );
                process_cpu.NextValue();
                pcList.Add(new Tuple(pg.First().ProcessName, process_cpu));
            }
            else
            {
                int id = 1;
                foreach(var p in pg)
                {
                    var process_cpu = new PerformanceCounter(
                           "Process",
                           "% Processor Time",
                           p.ProcessName + "#" + id
                                );
                    process_cpu.NextValue();
                    pcList.Add(new Tuple(p.ProcessName + "#" + id, process_cpu));
                    id++;
                }
            }
        }