Agama UX: It's very hard to switch away from Btrfs

[shundhammer]

Problem

The storage proposal defaults to a Btrfs root filesystem, but I don't want that: I want an Ext4 root filesystem.

But it's very hard to change the root filesystem from Btrfs to anything else:

First attempt: Trying to click on "Btrfs root partition with snapshots (at least 17.5 GiB)" in the "Partitions and file systems" box: Nothing. This is not clickable.

Second attempt: Trying to click in the table in the "Final layout" box: Nothing. Neither "Btrfs Partition" nor "New" nor the whole line is clickable.

Hm. This is getting awkward. What could be clickable here?

Let's try the "Change" button in the "Installation device" box. Well, yes, but all I can do there is select a different disk; or I could if I had a different one. No way to change the filesystem type from there:

Is it in the "storage techs" combo box? No, I can only select "iSCSI" here to use a networked disk that is available via iSCSI.

---

OK, back the the "Storage" main screen.

Let's try the "Change" button in the "Actions" box:

Hm... it's not the first three options. Let's try "Custom".

OK, now we have a list of (alread existing) partitions on that disk. But hey, at least we are down on the partititions level now.

This looks promising, but a look at this page's heading shows that it's about the "Space policy". There is nothing about the filesystem type; I can only decide for each partition to leave it alone, to shrink it, or to delete it. That's all very fine, but not what I want; I want to make a decision about the new partitions, not about the old ones.

---

Back again to the "Storage" main screen:

Okay; what else could be clickable here? - Hey, there is a ">" to the right of the "Partitions and file systems" header; I totally overlooked that one. Let's try it.

Duh. I should have known; it expands to this:

Okay, now we are in business: This is the new partitions layout. And for a change, there is a menu indicator (though very subtle) at the right of each partition; let's try that. We have a menu with "Edit" and "Change location".

Let's try "Edit":

Eh... I can change the size of that partition, okay. But that's not what I want; I want to edit the root filesystem type. But "Btrfs" here is also not clickable.

WTF?! Am I dealing with a product that enforces the root filesystem to be Btrfs? Seriously? I selected "Slowroll"! I could understand it for MicroOS with its transactional filesystem, but not for Tumbleweed or Slowroll!

What's going on here? Let's go back again.

It couldn't possibly be... no, I flatly refuse to believe that. But let's try anyway:

Let's switch that "Use Btrfs snapshots for the root filesystem" selector to "Off", and then try "Edit" on the root filesystem again:

Argh!

Okay, now I know how to do this: Switch off snapshots first, then you are free to change the root filesystem type. But it shouldn't be like that. That checkbox for the snapshots used to be a subordinate thing in YaST, and for a good reason: The root filesystem type is the primary selection, and snapshots are dependent on that selection.

Now the snapshot is the primary thing, and of course, when snapshots are an absolute requirement (as they are in MicroOS, for example), that requires Btrfs.

But this is the tail wagging the dog. This is unnatural and unexpected, not only for users who have previous experience with YaST, but also for users coming from Windows or from non-SUSE distros.

And this violates one of the holy grail principles of UI design: Don't surprise the user. Do the expected thing, not the unexpected, surprising thing.

[shundhammer]

This is not a contrived thing, it happened to me in real life.

[dgdavid]

Thanks HuHa.

Sure, we do not want surprise the user. Believe me :) I do not remember the details why Btrfs Snapshots ended up as a primary thing, but I remember there were a lot of discussion around the topic.

Fortunately, as you already know, we're working on an storage page revamp. It will not be perfect in the first release, but we hope to deliver something more easy to use and improve from there little by little.

So, with a bit of luck we are going to simplify the Btrfs thing too.