Im having performance problems when using the new VMWare native AHCI-driver on several hosts (Intel Avoton and also Xeon 1225 V3 System (HP Ml310e gen8)).
Using SSDs on those systems - im not sure if it also affects HDDs.
Moving back to the legacy vmklinux AHCI-driver fixes the problems.
See this blog post:
NXHut - IT and Windows - News: Fix slow disk performance (vmw_ahci driver) in ESXi 6.5
I hope this gets fixed soon so I can move back to the native drivers