SteamOS for the Steam Deck gets slimmed down to 10GB

Quoting: HoolyI think so too, they are probably using an A/B-model, which means that you have two installations of the OS at every time
[...]
Or they use btrfs-subvolumes and allocate storage dynamically.

Not exactly, they run on ostree, like Fedora Silverblue. It's a bit like a git repo, or guix/nix. It has deduplication, rollback, versioning, atomic updates. That's really promising tech, I'd have picked the same.

Let's try to come up with a basic estimate

• Base Arch Install: 100 MiB


• LLVM plus mesa: 300 MiB


• Web browser: 200 MiB


• Steam: 300 MiB


• Proton: 600 MiB


• KDE Plasma plus base KDE applications: 2 GiB


• Base Flatpak runtimes (freedesktop.org, VAAPI, mesa): 700 MiB

Total: 4.2 GiB. I'm falling short, but there could be more pre-installed software like Discord, plus probably a boot partition (might be a btrfs subvolume, not sure which FS they use), and possibly a "system restore" partition that might double the size, although I would personally make that a webinstall at about 150MiB.

Any other ideas?


Last edited by MayeulC on 16 December 2021 at 1:46 pm UTC

Maybe someon running Silverblue (or an OS-Tree Distro) with KDE could give use some stats.
Also there's the posibility that the apps they bundle use different flatpak platforms (even though these should de-duplicate) adding to the disk usage, but really having two images (so in case the main one breaks you can roll back to the previous, not sure if this is how ostree works really) sounds a sensible thing to do.

I was also wondering, if Valve will start publishing Steam officially over flathub.org at some point?

Edit: Looking at Endless OS download ISOs https://endlessos.com/download/ They are between 14GB ~ 20GB, I know they are GNOME based, but still a good reference I'd say, although they seem to bundle a lot of software/tools.

Here the output of `df -h` on a Endless OS Live Image (from distrotest.net) if anyone is curious:
live@endless:-$ df -h 
df: /run/user/1000/doc: Operation not permitted
Filesystem                 Size Used Avail  Use% Mounted on 
devtmpfs                   1.5G    0  1.5G    0% /dev 
tmpfs                      1.5G  84K  1.5G    1% /dev/shm 
tmpfs                      597M  40M  558M    7% /run 
tmpfs                      5.0M    0  5.0M    0% /run/lock 
/dev/mapper/endless-image3  31G  31G  454M   99% /sysroot
eos-live-boot              597M  40M  558M    7% /boot
eos-live-etc               597M  40M  558M    7% /etc 
eos-live-var               597M  40M  558M    7% /var 
tmpfs                      1.5G    0  1.5G    0% /tmp 
ens-live-sry               597M  40M  558M    7% /sry 
eos-live-sysroot/home      597M  40M  558M    7% /sysroot/home 
eos-live-sysroot/ostree    597M  40M  558M    7% /sysroot/ostree 
tmpfs                      299M 188K  299M    1% /run/user/1000
/dev/sr0                    18G  18G     0  100% /run/media/live/Endless-OS-4-0-0-en


Last edited by minkiu on 16 December 2021 at 2:16 pm UTC

Quoting: SolitaryWho knows, the question is what/why was it 24GB big before and how they managed to save 14GB.

Maybe they used to have a whole distro with every irrelevant lib and app installed, then went and trimmed that. Like I think LibreOffice is installed by default on many distros, but obviously the deck doesn't need that.

Quoting: ShabbyXMaybe they used to have a whole distro with every irrelevant lib and app installed, then went and trimmed that. Like I think LibreOffice is installed by default on many distros, but obviously the deck doesn't need that.

It's Arch, it doesn't have anything "irrelevant" preinstalled.

Quoting: HoolyOr they use btrfs-subvolumes and allocate storage dynamically.

Unlikely, since BTRFS does not have casefolding which Proton uses. Casefolding for now is only available with ext4.

Quoting: axredneck

Quoting: ShabbyXMaybe they used to have a whole distro with every irrelevant lib and app installed, then went and trimmed that. Like I think LibreOffice is installed by default on many distros, but obviously the deck doesn't need that.

It's Arch, it doesn't have anything "irrelevant" preinstalled.

It's not Arch. It's SteamOS, which is arch-based. It can, and likely will, have plenty of "irrelevant" libraries, since Valve will no doubt be thinking of use-cases we have no sight of just yet. It could be literally crammed full of what we'd consider to be irrelevant baggage.

SteamOS is the only one losing weight in December.

Quoting: MayeulC

Quoting: HoolyI think so too, they are probably using an A/B-model, which means that you have two installations of the OS at every time
[...]
Or they use btrfs-subvolumes and allocate storage dynamically.

Not exactly, they run on ostree, like Fedora Silverblue. It's a bit like a git repo, or guix/nix. It has deduplication, rollback, versioning, atomic updates. That's really promising tech, I'd have picked the same.

Let's try to come up with a basic estimate

• Base Arch Install: 100 MiB


• LLVM plus mesa: 300 MiB


• Web browser: 200 MiB


• Steam: 300 MiB


• Proton: 600 MiB


• KDE Plasma plus base KDE applications: 2 GiB


• Base Flatpak runtimes (freedesktop.org, VAAPI, mesa): 700 MiB

Total: 4.2 GiB. I'm falling short, but there could be more pre-installed software like Discord, plus probably a boot partition (might be a btrfs subvolume, not sure which FS they use), and possibly a "system restore" partition that might double the size, although I would personally make that a webinstall at about 150MiB.

Any other ideas?

Where did you get a base install size of 100MiB? Granted, I am on Ubuntu but

• the minimal kernel alone (no modules) requires 110MB of disc space. Add some kernel modules, firmware, basic libraries and GNU tools...


• Browser? Which one? Firefox comes in at around 250MiB, Chromium is considerably larger.


• Steam? Runtime and libs - we are getting into GiBs without any Proton version (bin32 - 800+MiB, bin64 - 300MiB,...)


• Mesa? The 64bit libgl1-mesa-dri reports 456MB, the i386 version 439MB plus Vulkan drivers. llvm clocks in at 100MiB per architecture.

That's Ubuntu, but I seriously doubt that Arch can do with a mere fraction of these binary sizes.

Quoting: win8linux

Quoting: HoolyOr they use btrfs-subvolumes and allocate storage dynamically.

Unlikely, since BTRFS does not have casefolding which Proton uses. Casefolding for now is only available with ext4.

Hmmm I actually use proton on top of btrfs, what issues will this cause ? Can I assume some of my games are broken because of that ?

i hope this 10GB include proton installations.
it make a lot of sense:
valve save bandwitdh by not having to distribute proton alongside the games for everyone who purchase an steam deck, instead it already come pre installed.
and it make it easier to manage.
just think about it:

lets say we have 2 games that use 100MB of storage and need the same version of proton to run, lets say: proton 6.3 (34MB)

the user will be confused if he see this situation:

you need 134 MB to install game A, and 134MB to install game B.
but if you have A installed you only need 100MB to install B, and if you have B installed you only need 100MB to install A.
if you only unistall one game, you free'd 100MB of disk space, but if you unistall both you free 234MB.
those games arent even from the same company to share any code/assets, so that problem dont make any sense for the end user, it just make it more confusing to manage your remaining storage.

10GB is A LOT of space for an linux distro, so i hope it also include some space for cache , for games/applications who need virtual ram, since 8GB might not be enough for then, and/or an copy of the OS as it came from factory for those who want/need to reset to factory settings.


Last edited by elmapul on 16 December 2021 at 4:56 pm UTC