Nutanix AHV: Where have all the memory gone?

In an AHV host with just the CVM and two other VMs running, there’s just about 1G of free memory. There’s 28 GB for the CVM and 8 GB each for the two other VMs. That is just 44 our of 125 GB of RAM on the host.

[root@ahv ~]# head /proc/meminfo
MemTotal:       131859556 kB
MemFree:          286384 kB
MemAvailable:    1151500 kB
Buffers:          113908 kB
Cached:           632172 kB
SwapCached:            0 kB
Active:           839356 kB
Inactive:           5600 kB
Active(anon):     106800 kB
Inactive(anon):      148 kB

This is because, from AOS 5.0, almost all memory is assigned to hugepages.

[root@ahv]# grep Huge /proc/meminfo
AnonHugePages:         0 kB
HugePages_Total:   63360
HugePages_Free:    40832
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB

This host has 123 GB (HugePages_Total * Hugepagesize) assigned to huge pages!

What are huge pages? How are they different from normal page?
See here

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