What is the primary function of the VMware Tools balloon driver?

The VMware Tools balloon driver plays a crucial role in enhancing a virtual machine's memory management capabilities. This driver enables the efficient management of memory resources by allowing the hypervisor to reclaim memory from a virtual machine when it is under memory pressure.

When a host system is running low on physical memory, the balloon driver can "inflate," which essentially means it requests the VM to give up some of its allocated memory by making it available for other virtual machines. This process helps in maintaining overall system performance and stability when the host needs to balance memory usage across multiple VMs.

In scenarios where workload fluctuation occurs, the balloon driver assists in dynamically managing the memory assigned to virtual machines, avoiding performance degradation caused by excessive memory contention. Thus, the balloon driver is critical for optimizing resources within the VMware environment, ensuring that virtual machines operate efficiently even under heavy demand.