We are on vSphere 6.5 and our Storage is HPE 3PAR 7400 SAN with Fiber-Channel (FC) and Near-Line (NL) type storage volumes.
I am creating and resizing existing Datastores to more standardized format. I am not sure what is the best size recommended when creating Datastore. I got to know from our Technical vendor that VMware best practice says Datastore size should 2TB. We have many VMs in existing VMFS5 Datastores, and if we are creating new VMFS6 Datatores with just 2TB each, then we will be needing many Datastores, each of those will only be able to hold few VMs. We also need to make sure there are a minimum recommended free space available (say 15%) all the time, so the more small Datastores, the more waste of storage. There are some VMs even that wont fit in one 2TB Datastore, rather will need few.
Our previous Datastores of VMFS5 type are in different sizes, between 2TB and 10TB, based on similar types of VMs present in one single Datastore. For example, for an application's production Environment, if there are 6 VMs, Datastore was created for that purpose and all VMs are in that. Off course over time it was expanded as VMs grew. While I don't think a 10TB is a good choice, neither a 2TB.
I have gone through " vSphere Storage - VMware vSphere 6.5 - VMware Docs" and "Performance Best Practices for VMware vSphere 6.5", haven't seen anything specific to what I am looking for if not missed.
Also need to know recommendations for HPE 3PAR SAN Virtual-Volume side.
Depends a lot of what types environments/workloads are you going to run on them. But i'd rather have more LUNs with smaller size - 4TB for example, which gives you also more flexibility.
"Also need to know recommendations for HPE 3PAR SAN Virtual-Volume side." - that's something you should check with them
So is it an advantage to have smaller Datastores of 2 - 2.5TB size over larger ones (5 - 10TB) in terms of efficiency and performance because each Datastore will have its individual LUN for transfer and storage operation into SAN?
For example, we have a SQL server with 7 disks for SQL data/log etc. Is it better to use individual Datastores for each of the drives to gain more read/write performance or IOPs than using single large Datastorer where all disks are in there? All Datastores will be connected to SAN using Fiber-Channel, and SAN physical Disks are 10K RAID6.
The drawback of using multiple small Datastore what I can think of is manageability and waste of disk-space since each Datastore has to have a minimum free-space.
I'd go for datastore up to 4-5TB. One of the benefit is that you can have SDRS.