Simulation running slow, quarter real time

edit

Other symptoms include:

• Not all the cores on the computer are working. Testable with: cat/proc/cpuinfo

• The following code has 4 ms intervals

  #include <sys/time.h>
  #include <time.h>
  #include <stdio.h>
  
  main()
  {
    struct timeval tv;
    struct timeval tv_old;
    gettimeofday(&tv, NULL);
    tv_old = tv;
    while(1)
    {
      gettimeofday(&tv, NULL);
      if (tv_old.tv_usec != tv.tv_usec)
      {
        printf("%ld %ld\n", tv.tv_sec, tv.tv_usec);
        tv_old = tv;
  
        // sleep 1 nano second
        struct timespec nsleep;
        nsleep.tv_sec = 0;
        nsleep.tv_nsec = 1;
        nanosleep(&nsleep, NULL);
      }
    }
  }
  

##Solution - Edit /etc/default/grub and remove acpi=off - sudo update-grub - restart