Question about locking memory in VMware host.

Hello i have a question about locking memory issue in Vmware Esxi 5.5.
I have a host with 64 GB RAM. I want to lock all memory to one VM. When i did it and want to power on VM, error with insuficient resources blocking the VM from start. Then i try and realize that i can reserve only about 58 GB of memory and the VM turns on. It is normal? Where is the rest of memory? It is used by vmware?

Thank you.
Pavol VrabecAsked:
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Andrew Hancock (VMware vExpert / EE MVE^2)Connect With a Mentor VMware and Virtualization ConsultantCommented:
Firstly this is TOO BE expected, and usual behaviour.

The Hypervisor requires some memory to operate, also for every VM, there is also a memory overhead, required by the hypervisor to execute the VM.

So Hypervisor requires memory for it's OS + Memory overhead for the VM, to satisfy 64GB is probably greater than 64GB.

If you want to allocate ALL memory in the host to a VM, why use a hypervisor ? Install on bare metal or increase memory in the host.

it may not be a good candidate for virtualization, considering the cost of the hypervisor license!

Memory Reservation is the function to use, because it GUARANTEES memory for the VM, e.g. ring fences the memory resource, so no other VM can take memory away from the VM, whether that VM is using all the memory or not it does not matter.
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Pavol VrabecAuthor Commented:
Yes i know but later we want to buy additional resources and add another VMs. So thank you now i understand the problem.
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Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
No problems.
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