Vmware balloon driver disable

VMWare is able to share identical memory between machines, so if the balloon driver reserves memory identically over a number of machines, the host only has to store one copy of this in memory. This can give a substantial lift to memory usage efficiency. What the balloon driver does is to take up memory to simulate memory pressure on the virtualised server.

Windows running on the guest OS then determines what is unnecessary to be in memory and pages it to disk. If the server requires more memory, the balloon should deflate a little.

This ensures that the guest OS only has as much memory as it needs, and very little is wasted. However, what happens when SQL Server starts?

However, the balloon driver now conspires to keep memory pressure on, and as SQL Server believes that there is no free memory available, it will not increase its memory usage. It means the virtual memory for the virtual machine may be swapped to disk, massively slowing down both the guest and the host computers. It is the amount of memory that is presented to the guest operating system, but it is independent of the amount of physical RAM that is allocated to the virtual machine , which depends on the resource settings shares, reservation, limit explained below.

Press space to return to the main memory view page of esxtop. In the vSphere Client, right-click a virtual machine from the inventory and select Edit Settings. In the Resource Allocation panel, select the Reserve all guest memory All locked check box.

Click OK. Consumed Host Memory usage is defined as the amount of host memory that is allocated to the virtual machine. Active Guest Memory is defined as the amount of guest memory that is currently being used by the guest operating system and its applications.

Virtual memory ballooning is a computer memory reclamation technique used by a hypervisor to allow the physical host system to retrieve unused memory from certain guest virtual machines VMs and share it with others.

Memory overcommitment explained. Memory overcommitment is a process of allocating more memory for VMs than the host physically has. For example, if you have an ESXi host with 6GB memory and run five virtual machines with 2GB memory each, the host machine's memory is overcommited. Ballooning is an activity that happens when the ESXi host is running out of physical memory.

The demand of the virtual machine is too high for the host to handle. This driver then consumes some of the memory that the guest OS believes is physically present in the virtual machine. Disabling balloon drivers can be done by editing the configuration parameter of the virtual machine. Power down the virtual machine. Right Click the virtual machine and click Edit Settings. Dynamic Memory for a single virtual machine has three allocation values: Minimum, Startup, and Maximum.

The Startup memory is what will be allocated to the guest at the moment that it is turned on. That amount will be immutable until the Dynamic Memory driver in the guest successfully communicates with Hyper-V. Procedure Browse to the host in the vSphere Web Client navigator. Click Configure and expand Hardware. Select Processors to view the information about the number and type of physical processors and the number of logical processors. If a Kubernetes worker node is inactive or running at a lower utilization-rate, these resources are allocated to other active Kubernetes worker nodes within the same resource pool.

Resource Pools and Kubernetes are a great fit together, however, resource pool sizing must be adjusted when the Kubernetes cluster is scaled out with new workers. If the resource pool reservation is not adjusted, resources are allocated in an opportunistic manner from the cluster, possibly impacting predictability and consistency of resource behavior.

Non-overcommitted Physical Resources Some vSphere customers design and size their vSphere clusters to fully back virtual machine memory with physical memory. This can be quite costly, but it does reduce operational overhead tremendously.

The challenge is the keep the growth of the physical cluster aligned with the deployment of workload. Overcommited Resources But what if this strategy does not go the way as planned? What if for some reason resources are constrained within a host and the VMkernel applies one of its resource reclamation techniques?

One of the feature that is in the first line of defense is the balloon driver. Designed to be as non-intrusive as possible to the applications running inside the VMs. When memory is over-committed the ESXi server reclaims memory by instructing the balloon driver to inflate by allocating pinned physical pages inside the guest OS.

This causes memory pressure within the guest OS which invokes its own native memory management techniques to reclaim memory. Balloon driver then communicates these physical pages to the VMkernel which can then reclaim the corresponding machine page.

Deflating the balloon driver releases the pinned pages and frees up memory for general use by the guest OS. The interesting part is the dependencies of guest OS native memory management techniques.

As a requirement, the swap file inside the guest OS needs to be set to disabled when you install Kubernetes. The swap file is the main reason why the balloon driver is so non-intrusive.

It allows the guest OS to select memory page it deems fit. Typically these are idle pages and thus the working set of the application is not affected. What happens if the swap file is disabled. Is the balloon driver disabled? The answer is no. Just to be sure I used another command swapon -s. Both outputs shows no swap file. The command vmware-toolbox-cmd stat balloon shows the balloon driver size.

The command vmware-toolbox-cmd stat balloon confirmed the output of the stats showed by vCenter. The balloon driver pinned 4GB of memory within the guest.

OOM stands for out of memory.