Regarding vSAN 6.7 memory consumption calculations,
I am trying to calculate the vSAN overhead / memory calculations for a 4 node VxRAIL E560F cluster. Each node has the following configuration:
CPU | VXR INTEL CPU GD 6238 2.1G 22C | 1 x Physical CPU = 22 Cores |
RAM | VXRAIL MEMORY 32GB 2933MT RDIMM | x12 32 GB RDIMM Modules |
Cache Devices for vSAN | VXR MIXED USE 800GB 2.5 CACHE | 1 x 800 GB SSD |
Capacity Devices for vSAN | VXR 1.92TB CAPACITY SATA 2.5IN SSD | 2 x 1.92 TB |
There is a KB article out: https://kb.vmware.com/s/article/2113954. In this article they describe (for example) that you can calculate an all flash configuration with 1 disc group with the following formula:
HOST_FOOTPRINT + NumDiskGroups * (DISKGROUP_FIXED_FOOTPRINT + DISKGROUP_SCALABLE_FOOTPRINT + CacheSize * CACHE_DISK_FOOTPRINT + NumCapacityDisks * CAPACITY_DISK_FOOTPRINT).
They say at the beginning that with all flash systems, the DISKGROUP_SCALABLE_FOOTPRINT = 0.5% of system memory.
In the examples they give a host with 256GB memory as an example. 0.5% of 256GB is 1,28 or 128000MB.
In the examples they have 1310 and 1228 for their DISKGROUP_SCALABLE_FOOTPRINT. Not sure how they are getting this number at all.
Maybe I have missed something fundamental here? Any assistance is very much appreciated
Thank you