Configuration

• Check number of cpu cores in your virtual machine
  • cat /proc/cpuinfo
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• You can find "cpu cores: 1" in the output after you run cat /proc/cpuinfo, which denotes that in your ubuntu virtual machine, you only have one cpu core.
• Check the memory capacity in your virtual machine
  • right click your virtual machine -> "Settings" -> "System" -> "Motherboard"
  • 
  • We can see the default memory capacity is 4MB
• Log out and re-configure virtual machine
  • right click your virtual machine -> "Settings" -> "System" -> "Prosessor"
  • modify "Processor(s)" to 4, or any number you want
  • "Settings" -> "System" -> "Motherboard"
  • click "ok" ant start your virtual machine and now you find the number of cpu cores is 4. And the base memory is 1024MB