Can I load test my server?

Currently have 4 servers running. Velocity proxy, survival, skyblock, and creative. The 3 playable servers are Paper 1.21.4

I want to find out if my homelab Unraid server can handle the workload.

I am using a dell optiplex 3070 SFF. If I recall correctly its got an i5 9500, 16gb DDR4 at 2600 mhz, an NVME drive as cache (also where my dockers such as crafty-4 are stored), alongside a 1TB HDD. I will soon be upgrading to two 4TB drives to use parity for redundancy. I am also considering using my older Ryzen 2700 processor since it has more cores (I run other dockers such as plex, jellyfin, general media stuff, etc). My concern is that I've been told Minecraft performs better with single core performance, so switching CPU/mobo would provide much benefit specifically for Minecraft. Oh and the ram would be upgraded to 32gb at 3200mhz.

Benefit of switching to the Ryzen 2700: Increased core count, better balance for all the other dockers running, AND equal TDP so should be roughly the same power consumption
Downside of switching to the Ryzen 2700: Potentially worse performance for MC servers.
As of now, Crafty-4 is pinned to only cores 4 and 5 (2 of 6 cores), and I have allocated 6GB of ram solely to Crafty-4
This also means that I would be able to allocate more cores to crafty-4 as the Ryzen 2700 has 8 cores 8 threads whereas the i5-9500 only has 6 cores.

Anyways, I'd love a way to stress test without having an actualy player load on each server. I've seen spark reports from other questions but I am not sure how much insight that will provide with 0 players on each server.

Thanks, sorry for the loaded question(s)!