Resource Reservation

[asvidra]

What is resource reservation in vmware ?

Having 2 ESXi in my environment, each has 10 vm's in it.

In the 10 vm's, 3 are crtical and they need 3GB rams always.

How to achieve this ?

Kindly give a brief description to understand the concept of resource reservation in vmware. Please dont share any links to see since have already tried but still confused in my mind....

[a_p_]

vSphere provides different options to reserve resources. Either by using Resource Pools or by reserving memory and/or CPU for an individual VM. However, this should only be considered if you are low on resources, because the reservation has effects on e.g. HA depending on the Admission Control settings (slot size).

André

[joshodgers]

The use of reservations is generally only required where memory (or CPU) over-commitment is such that one or more VMs are suffering contention such as ballooning or swapping.

If the VMs are not experiencing swapping or ballooning, check the Active memory verses consumed, and you will likely find the active is much lower than consumed.

The above comments above reservations affecting the HA admission control calculations are also correct, as such avoid reservations unless absolutely required.