On your home desktop, you don't have to run dedup. You will get still the bitrot protection.
I hate the cargoculting on this fucking site.
On a desktop?
Chances are, that you don't have many users saving the same or slightly modified version of a file on the same storage. For a single person, it doesn't make much sense.
> "You can use ZFS just fine, just turn off one of its most useful features."
ZFS has many useful features. They come with a price though, because there's no free computation (see also laws of thermodynamics). It is then a matter of deciding, which features you want or need, and are willing to pay the price for.
You obviously are not willing the pay the price for dedup (lvmvdo asks for similar price, so it is not ZFS-specific), so why are you complaining that you cannot use it? ZFS still has many more useful features.
You also have another option: add RAM to your desktop. It is cheap. Then you will be able to use that one feature.
> I hate the cargoculting on this fucking site.
Sigh. I'm actually btrfs fan, all my data are on a btrfs volume (at work, we do use ZFS though, so I do have the experience). But that doesn't mean I won't point out something that the other club does well.
Please explain where this number comes from. I run ZFS on boxes with as little as 4GB of RAM, which are also doing all sorts of other things in addition to ZFS.
As with all filesystems on Linux, more RAM means more cache, and if you have free RAM you will benefit from a dynamically resized filesystem cache. That RAM is however not required and the cache can be evicted under memory pressure.
ZFS will use all available RAM for caching, unless you tell it otherwise (zfs_arc_max[1] or similar[2]), but it should release it when the system requires it[3].
[1]: https://docs.oracle.com/cd/E19253-01/817-0404/gjhec/index.ht...
I did briefly try ZFS on my laptop a year or so ago, and it ate up half of my RAM permanently. Since it was already fairly limited, that wasn't a sacrifice I wasn't willing to make either when I have plenty of backups anyway.