I need to create two 9 TB file systems and i am struggling to design it. how does fsck work under the cover?

I have two options:
1. I create two 9TB LUNs at storage and create VG on them and then create LVs of 9TB each to create file system of 9TB each
2. I create 9 2TB LUNs at storage and create VG on them and then create LVs of 9TB each to create file system of 9TB each

what option from above will take less time for fsck to run?
is there a fsck check during system boot? which of the above options are helpful to minimize the file system check during boot if any?
is there anything else that i am missing here?

Do you actually -=need=- LVM?
Does disk space need to be allocated on the Fly?
What are your actual disk space requirements?
Are these systems susceptible to brown / blackouts / fat-fingering?
Are they connected to a UPS?

LVM is not mandatory. disk space will be used for oracle. i need to create file system before installing oracle.
those are my actual disk space requirements i.e. total 18TB
these are going to be enterprise system and risk levels are same as with any enterprise systems. they are in enterprise data center and i am pretty sure there is UPS

So there you have it. Your actual requirement is only having a 18TB slice regardless of the means you gonna create it with.

fsck is at a filesystem level, so it doesn't matter if it's 2*9T, 9*2T, or 90*200G. The time to fsck is dependent on the filesystem size.

On the topic of LVM, we support 800+ systems and life would be hell without LVM. In terms of SAN, LVM will allow you to migrate data off of one LUN and onto a new one when you replace an old storage unit, etc. You can add additional PV's on the fly and resize existing LV's (upwards, at least with ext2/3/4). There is no measurable performance hit. And LVM2 is pretty solid. That being said, 9TB is an awful amount of data. I'd be nervous with 9TB LUNs. But doing a consistency check of LVM metadata on a lot of small LUNs (like when the LVM is activated at boot time) is not a desirable situation either. Do you have time to play with this? Do a "proof of concept" before you cast your design in concrete?

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