What disk layout to choose for soft-raid'a?

Question

linux

Colleagues, good day!
A "server" with 3 disks (HDD) with a volume of 1TB fell into the hands. Task: install Ubuntu Server 18.04 on it, combining disks into a single space. It is highly desirable to do this in the "striped" mode (RAID-0, there are no reliability issues, there will be no valuable data there).
During installation, Ubuntu Server offers two options for this task:
1. mdadm
2. LVM
I figured out option 1, everything is quite simple. Incl. you can choose the array mode and other options... Difficulties arise with LVM. In particular, I cannot find answers to the following questions for myself:
1. Which option is more suitable in this case and why? I'm more impressed with the LVM option.
2. When manually partitioning LVM, I can specify the mode in which the volume (logical disk) will be added, for example, lvcreate -i3in disk partitioning mode when installing Ubutnu server 18.04, for some reason this is not possible. Or I just didn't find it?
3. Is there any way to install the entire system on a ready-made soft-raid (lvm/mdadm), without allocating separate pieces (partitions) for booting, etc.? As far as I remember, GRUB2 already knows how to boot from such "carriers", but I did not find such an opportunity "out of the box" when installing Ubuntu Server 18.04. Please tell me the shortest (simplest) way to implement this task.
PS I would be grateful for any information "on the topic" and links to acc. resources. An independent search for answers in this case did not allow me to clarify many questions.

Answer 1

You forgot the option with btrfs, loading 'from a folder', support for all kinds of raid analogs, no extra layers, productive snapshots, a common single space for all partitions (subvolumes), compression and theoretical support for deduplication (normal software is only in beta versions, compile manually ).
In general, if you do not need lvm encryption, you will no longer need it.