VMware Player online course

Change a Virtual Machine's Memory Allocation in VMware Player

Learn how to change the RAM assigned to an existing VMware Player virtual machine, choose a safe amount, and troubleshoot memory-setting problems.

What virtual machine memory allocation means

VMware Player is a desktop virtualization application. It runs a virtual machine (VM), which is a software-defined computer containing a guest operating system. The physical computer and operating system running VMware Player are the host system.

While a VM is running, it uses a configured portion of the host's physical RAM. This configured amount is the VM's memory allocation. More allocated memory can make the guest more responsive and allow it to run larger applications or more applications at once. However, that memory is no longer freely available to the host and its other applications.

Before you begin: fully power off the VM

The virtual machine must be completely powered off before you change its memory setting. Powered off means that the guest operating system has shut down and the VM is no longer executing.

A running or paused VM is not powered off. A suspended VM preserves its current runtime state so it can resume later, but it is also not equivalent to a powered-off VM. Depending on the version and state, the Memory setting may be unavailable or unsafe to apply while the VM is active.

Change the memory allocation

1. Open VMware Player and select the target VM in the library.

2. Confirm that the VM status is powered off. If it is running, shut down the guest normally. If it is suspended, choose the option to power it off instead of resuming it.

3. Open the settings window through this menu path:

   Player > Manage > Virtual Machine Settings > Hardware > Memory

4. In Virtual Machine Settings, open the Hardware tab. This tab contains virtual devices such as memory, processors, disks, and network adapters.

5. Select Memory from the hardware device list.

6. Use the memory value control or slider to choose the desired RAM allocation. Follow the sizing guidance displayed in the Memory panel.

7. In the described VMware Player interface, the configured value must be a multiple of 4 MB. If you enter a value manually, use a supported multiple.

8. Confirm or save the updated settings.

9. Power on the VM. The guest operating system receives the newly configured memory when it starts.

Choose an appropriate amount of memory

Begin with the guest operating system's minimum and recommended RAM requirements. Then allow additional capacity for the applications you expect to run inside the guest, such as development tools, databases, browsers, or media applications.

Also reserve enough RAM for the host operating system and other applications that must remain responsive. If multiple VMs run at the same time, their allocations compete for the same physical RAM.

• Guest too slow: Increase the allocation gradually if the host has enough unused RAM.
• Host becomes sluggish: Reduce the VM allocation or close unnecessary host applications.
• Several applications run in the guest: Allocate enough for their combined working needs, but do not consume nearly all host RAM.

Overallocating memory can degrade the host, the VM, and other running workloads. A larger number is not automatically faster if the host begins paging or lacks memory for its own tasks.

Historical per-VM limits and platform differences

The VMware Player version represented by this lesson documented these historical maximum allocations per VM:

Actual supported limits can depend on the VMware Player version, host architecture, host operating system, and available physical RAM. Historically, VMware Player did not impose a total configured-memory limit across all VMs, but that does not mean all VMs can run simultaneously at their maximum allocations. Concurrent use remains constrained by the host's resources.

Examples

Guest is slow with several applications open

Shut down the VM completely, open Player > Manage > Virtual Machine Settings, select Hardware > Memory, and increase the value while retaining adequate RAM for the host. Save the change and start the VM.

The host becomes sluggish after increasing allocation

Power off the VM, reduce its configured memory in the Memory panel, save the settings, and restart the VM. Also close unnecessary host applications or reduce the number of VMs running concurrently.

The VM is suspended when you try to edit RAM

Do not simply resume the VM. Fully power it off, then reopen Virtual Machine Settings and edit the Memory hardware setting.

Troubleshooting

The Memory option cannot be edited

The VM is probably running or suspended. Shut down the guest and ensure that VMware Player shows the VM as powered off before reopening Virtual Machine Settings.

The requested memory amount is rejected

Check that the value is a multiple of 4 MB in the described interface. Also check the applicable per-VM limit, host architecture, VMware Player version, and the amount of available physical RAM.

The host becomes slow after the change

Too little RAM may remain for the host operating system, or multiple VMs may be consuming memory simultaneously. Power off the affected VM and lower its allocation, close unnecessary host applications, or reduce concurrent VM usage.

The guest still reports the old amount of RAM

Verify the value in Virtual Machine Settings, save the configuration, and fully power on the VM again. The guest receives the new allocation at startup; changing the setting alone does not update an already running guest.

Next steps

For related virtual hardware tasks, see configure a virtual machine for compatibility and configure virtual SMP. For general terminology, review what a virtual machine is.