CompTIA DataSys+ (DS0-001)Database DeploymentMedium
A database administrator is planning the deployment of a new PostgreSQL database on a virtual machine. To ensure consistent and predictable performance, especially during peak loads, the administrator needs to configure the virtual machine's resources to prevent resource contention with other VMs on the same physical host. Which virtual machine configuration setting directly addresses this concern?
- ADynamic Memory Allocation
- BResource Reservation
- CStorage Thin Provisioning
- DCPU Overcommitment
Show answer & explanationAnswer & explanation
Correct answer: B. Resource Reservation
Resource Reservation allows the administrator to guarantee a minimum amount of CPU, memory, or I/O resources to a specific virtual machine, regardless of the demands from other VMs on the same physical host. This prevents resource contention and ensures predictable performance for the critical database.
Why the other options are wrong
- A. Dynamic Memory Allocation (or memory ballooning) allows the hypervisor to reclaim unused memory from VMs, which can lead to unpredictable performance for critical applications.
- C. Storage Thin Provisioning allocates storage space on demand, which is efficient but does not prevent resource contention for CPU, memory, or I/O bandwidth.
- D. CPU Overcommitment allows the hypervisor to allocate more virtual CPU cores than physical cores, increasing host utilization but risking CPU contention and performance degradation for all VMs.
VM Resource Reservation
A configuration setting in virtualization platforms that guarantees a minimum amount of CPU, memory, or I/O resources to a virtual machine, preventing resource contention.
- Ensures predictable performance for critical VMs.
- Prevents resource starvation caused by other VMs.
- Reduces hypervisor overhead in allocating resources.
Memory trick: To guarantee performance, reserve the resources you need.