How important to passthrough RAID to VSAN VM?

[Automate]

This page https://knowledgebase.starwindsoftware. ... ssd-disks/ says:
NOTE: For configurations where StarWind VSAN service is running inside a virtual machine, it is recommended to passthrough RAID or HBA controller to the virtual machine.

I have 2 Dell R750 servers with PERC H755 controllers and 8 1TB SSD (per server) configured as a single RAID 5. Running ESXi 6.7. from mirrored SD cards.

How much of a performance hit will I see by not passthrough the RAID to the VSAN VM?

[yaroslav (staff)]

Greetings,

Welcome to StarWind Forum. Please note this question to be rather related to ESXi than to StarWind VSAN. There should be performance penalty coming from the additional virtualization i.e., (datastore and VMDK).
Alternatively, it is possible to present the storage as an RDM disk.

[Automate]

Alternatively, it is possible to present the storage as an RDM disk.

Will RDM provide similar performance to RAID controller passthrough?

[yaroslav (staff)]

You are right. It will have similar but not exactly the same performance.