Manual Partition Help - sizing and selection

General system EndeavourOS installation
1

My current partitioning is 4GB for a Limine boot partition and 1TB BTRFS parition for CachyOS with subvolumes.

What’s the best practice? Reuse the existing btrfs partition and reformat, or create separate root and /home partitions?

If separate, how large should I make the root partition?

I plan on installing snapper and using snapshots, so that may or may not effect how to setup the partitions.

with 64gb of ram, and my plan is to use zswap, like cachyos, I don’t think I need a swap partition

Edit: I have existing partitions that I don’t want to touch, to the automated portion of the install doesn’t fit my needs.

2

I always create separate / and home partitions because I like to reinstall without affecting my data. At the moment, they’re even on separate drives!

3

What about sizing the /root? 40GB?

4

If your goal is to replace your current OS and wipe the whole drive, I would suggest you to go with automatic install. Choose your filesystem and bootloader and let the installer take care of the partitioning for you.

Also, a small amount of a swap device is regarded as beneficial to memory management no matter how big a size your RAM is. I would choose a swapfile.

5

You may be OK with 40G but I do 100G to give me plenty of breathing room. Currently it’s 128G because of the disk it’s on. I admit that’s probably a bit too much!

6

I can’t there’s existing partitions that I don’t want to touch - I get your logic, and it makes sense. I should have put that in my OP

7

you can install only to the partition(s) you need. I have a laptop with one physical drive I split and the last time I did a reinstall i just had to add the extra partition to boot up using fstab. Took less than 15 seconds to setup my fstab. partitioned the old root drive and left the other drive alone (has about 500gb of music)

8

Alright, this is what I would do.

I would wipe the current OS partitions.

Not sure what the current recommendation is on EOS for the size of the ESP but Archwiki mentions at leas 1 GB up to 4 GB (here). This should be FAT32 and flagged as boot.

The remaining space, one whole Btrfs partition.

Choose manual installation and point the installer to these partitions.

The ESP should be mounted on /efi.

Th Btrfs partition should be mounted on /.

¡¡ Pay attention to not to touch your other partitions !!

9

Our default is 2 gig currently we recenty bumped that up from 1 gig.

10

You also do not have to use the installer to manage the partitions fully, you can use partition manager before starting installer and set everything as you like and in the manual partition of the installer only add the mountpoints without formatting in case.

11

I have a 2 disks setup, one contains home and boot partitions, the other disk has root and swap.
So while boot and home remain preserved, root and swap be exchanged by multiple replacment OSes. I could in future also persist the /etc and/or /srv, /opt partitions.