Configuring virtual machine memory and CPU

Modify virtual machine resource requirements such as virtual CPUs and memory to suit the changing needs of your environment.

Before you begin

You must be assigned one of the following permissions to configure virtual machine memory and CPU:
  • Cloud group administration role with permission to View all cloud groups (Read-only permission)
  • Resource level administration role with Write or All access rights permission (ACL) for a specific instance

About this task

You can use the console or the command line interface to complete this task. For the command line information, see the Related information section.

Procedure

  1. Access the console pane. Click Patterns > Virtual Machines.
  2. Select the virtual machine that you want to edit.
  3. Click the Configure icon on the toolbar.
  4. Complete the following fields:
    CPU count
    Specifies the number of virtual CPUs assigned to this virtual machine.
    Virtual memory
    Specifies the memory that is currently being used by the virtual machine. You can optionally specify the memory size in MB or GB.
    Important: When the virtual machine is powered off, the size of the change is only limited by available compute node capacity. The following guidelines exist when scaling the allocated memory or number of CPUs of a deployed virtual machine that is powered on. You might see the error CWZIP1987E in log files.
    • If you START with the initial CPU count value of 8 or greater, you must restart the virtual machine before you can incorporate a resize to the CPU count.
    • If you START with an initial count of less than 8 (1 - 7), hot resize within a running instance.
      Note: Hot resize up to four times within a running instance and up to a total of 16 cores.
    • Virtual machines that are currently running with more than 3 GB of memory can be changed to a maximum memory size of 4 times the size of the virtual machine's memory when it was powered on.
    • You can increase or decrease the memory on a running virtual machine up to 4 times the initial deploy setting. To increase or decrease the memory beyond 4 times, you must first stop the virtual machine and then make the change.
  5. Click OK.