Why do I use the Eager Zeroed type to configure MSCS?

[MICDROP]

Hi, all.

I'm studying disk provisioning type.

I was studying the difference between Lazy and Eager among thick provisioning, and I saw that performance is little difference between the two types.

It is said that using the Eager type is when using MSCS or VMware FT, can you tell me why?

I also wonder why we should use the Lazy type.

(Just to create a virtual disk a little faster?)

Thank you in advance for your advice.

Regards.

[scott28tt]

Some useful reading for you:

FT

Legacy Fault Tolerance​ (note the requirement for eager zeroed is no longer true)

WSFC (MSCS)

https://docs.vmware.com/en/VMware-vSphere/6.5/vsphere-esxi-vcenter-server-651-setup-mscs.pdf​ (note page 10 states eager zeroed is required)

VMware Knowledge Base  (note that eager zeroed is not required with vSAN)

And a few blog articles:

Death to false myths: The type of virtual disk used determines your performance | Yellow Bricks

https://frankdenneman.nl/2012/12/19/thin-or-thick-disks-its-about-management-not-performance/ 

Eager thick vs Lazy thick disk performance – Rickard Nobel