I'm new to btrfs and I'd like some advice on partitioning and subvolume strategy. The system is a light-duty web server, and assume it only has a single disk.
With ext filesystems, I've always created separate partitions for /, /var, swap (and possibly /boot and /home). For me, /var always contains all valuable web server data (e.g. MySQL databases) and none of the code. That allows me to easily move the data to a different system (move or copy /var) or re-install the OS without disrupting the data (reformat /) etc.
Using btrfs, I could do the same thing, use the same partitioning scheme, and have a separate btrfs filesystem on each partition. Or, I could have a single partition, and use btrfs subvolumes for /, /var and so forth. What would be the pros and cons of that?
It seems to me there may be some advantage in having /-only and /var-only snapshots, for example ("Restore all the data to a previous checkpoint" vs "restore all the code" vs "restore both"). Is that right, or does it only appear that way?
Bonus question: are there advantages to using lvm below the btrfs filesystem(s)?
Bonus question 2: how would your advice change if the system had two disks of the same size?
Any pointers to "this is what I did and how it has worked for me" articles would also be appreciated. I can find plenty of material on what I can do, but I'm failing to find much saying "this is what I tried and this is why it worked or didn't".