.net - Fastest & Least CPU intensive way to Get List of Running Processes with their Id and Location in C# -

i have written module gets list of running processes every 250ms windows xp , above. have tried .net & wmi way, both of them cpu intensive. both of them finish within 80ms on machine. host process cpu remains above 10 14 percentage in either case. think location/executionpath property real culprit. there better way information?

edit1: in testing - .net way more cpu intensive faster wmi way. - wmi way slower less cpu intensive since moved cpu usage wmi provider host

    private static int wmiway()     {         string wmiquerystring = "select processid, executablepath win32_process";         using (var searcher = new managementobjectsearcher(wmiquerystring))         {             using (var results = searcher.get())             {                 foreach (managementobject oreturn in results)                 {                     if (oreturn["executablepath"] != null)                     {                         _processes.add(new processinfo()                         {                             processid = (uint)oreturn["processid"],                             filepath = oreturn["executablepath"].tostring(),                         });                      }                  }                  return results.count;             }         }       }      private static int netway()     {         var processes = system.diagnostics.process.getprocesses();         foreach (system.diagnostics.process runningprocess in processes)         {              if (runningprocess.id > 4)             {                  try                 {                     _processes.add(new processinfo()                     {                         processid = (uint)runningprocess.id,                         filepath = runningprocess.mainmodule.filename,                     });                  }                 catch { }             }         }          return processes.length;     } 

finally decided go pinvoke route. in testing turn out best solution. did reduce cpu usage 2 percentage , faster .net or wmi way.

    private static int pinvokeway()     {         uint[] processids = new uint[1024];         uint bytescopied;         uint processcount = 0;         if (processapi.enumprocesses(processids, (uint)processids.length * sizeof(uint), out bytescopied) || bytescopied == 0)         {             processcount = bytescopied / sizeof(int);              (int = 0; < processcount; i++)             {                 string path;                  if (environment.osversion.version.major >= 6)                     path = getexecutablepathabovevista(processids[i]);                 else                     path = getexecutablepathxp2003(processids[i]);                  if (!string.isnullorwhitespace(path))                 {                     _processes.add(new processinfo()                     {                         processid = processids[i],                         filepath = path,                     });                 }             }         }         return (int)processcount;     }      private static string getexecutablepathabovevista(uint processid)     {                     var buffer = new stringbuilder(1024);         try         {             intptr hprocess = processapi.openprocess(processapi.process_query_limited_information,                                           false, processid);             if (hprocess != intptr.zero)             {                 try                 {                     int size = buffer.capacity;                     if (processapi.queryfullprocessimagename(hprocess, 0, buffer, out size))                     {                         return buffer.tostring();                     }                 }                                 {                     processapi.closehandle(hprocess);                 }             }         }         catch { }          return string.empty;     }      private static string getexecutablepathxp2003(uint processid)     {                     var buffer = new stringbuilder(1024);          try         {             intptr process = processapi.openprocess(processapi.process_query_information                 | processapi.process_vm_read, false, processid);              if (process != intptr.zero)             {                  try                 {                      if (processapi.getmodulefilenameexw(process, intptr.zero, buffer, buffer.capacity) != 0)                     {                         return buffer.tostring();                     }                 }                                 {                     processapi.closehandle(process);                 }              }           }         catch { }          return string.empty;     }