Help with node design - single physical cpu

[nicholasbird]

In our vsan design we are having to only consider single cpus in our 4 node cluster..as a charity we cant afford 2x vsan licensing per node.

(No idea why storage  license cost should be linked to physical cores, i guess it fits with esxi model)

We are considering 2683v4 1x16 core rather than  2 x 2620v4. (2.1 ghz).

We are assuming 10% of compute will be used for vsan storage.

We only have 40 vms. 10 of which are compute and burst storage greedy citrix workers.

Is a 1 cpu 16 core design valid for vsan  ( and esxi for that matter) or are we going to be hamstrung?

How much memory and compute per node is realistic?

We plan to use raid 1 and raid 5 vm profiles and enable dedupe and compression. Storage will be 1 disk group per node nvme pcie write tier 2xssd read tier.

Thanks for advice.

[zdickinson]

Good morning, this is a good doc regarding the overhead of the features in vSAN 6.2  https://www.vmware.com/files/pdf/products/vsan/vmware-vsan-62-space-efficiency-technologies.pdf

It says 5% for dedupe and compression, so I like overestimating the overhead.  Are you planning on erasure encoding?  That might push it to 10%  Also if you do RAID 5, there is more overhead during re-builds.

The problem with 1 socket is the memory is directly linked to a socket.  You'll have to pay attention to this as it can vary widely depending on the speed, size, and rank of memory.  In general I have found almost all work loads to be more memory intensive than CPU, so I would get as much memory as possible considering budget and host configuration.

Thank you, Zach.