I think I have (almost) complete explaination for the Samsung's System Files thing.

[Sooneung]

I read about the recent Galaxy's System Files article, and I wanted to find the reason behind this chaos.

I imported all partition information onto my PC and did some calculation. Since I'm no expert at this, some of info may not be correct or represent all devices.

 

My Conclusion in short:

As many of you guys have expected/guessed, it's just the storage size unit difference thing.

Android (and its root Linux) calculates storage and files in binary(MiB, GiB) but consumers are used to decimal units(MB, GB), so Samsung just decided to calculated in binary then add dummy numbers to hide the difference. I mean if they didn't do that, customers would be angry about smaller storage and complain about it wouldn't they? Even if Samsung and their engineers try their best to explain it, they won't be able to convince them.

On my calculation, the whole System Partition"S" are total 10.94GB. This includes system image itself, modem, hw specific libraries, carrier/country specific apps/configs, hw configs etc. Also, I think there are more hidden partitions for KNOX, other more secure things or critical system files. (This sum of partition sizes didn't add up to exactly 256GB. It's missing 2.43GB, but I bet Samsung cheaped out on that. I think it's hidden by KNOX or something.)

Here is the list:

- System Partitions: 10.94GB

- Missing Bytes: 2.43GB

- Unit Difference: 17.41

> Total System Files: 30.79GB (Including missing bytes)

> Reported System Files: 34.46GB

 

Now you may say that there's still 3.57GB left. I think this one's reserved for system caches and safe buffer. My guess is that Samsung wanted to leave some headrooms so that even if the customer fills up the storage to 100% device can still function, alerting user to delete some files, not locking itself up. OR, it's just cache/tmp files or combination of two. This theory is also somewhat backed up with the fact that actuall /data's usage is 4.74GB bigger than the Samsung's reported used space. Also, Samsung's Reported System Files size changes from time to time. Not because I updated the system. I left the device, calculating this storage thing, but it decided to change the size by itself. If the System partiton ONLY contains the Read-Only ROM, there's no reason for the value to be changed. (Fun fact: /system is ext4 RO, which means read-only. Other system partitions are the same too.) This backs the "Cache/Buffer" theory.

I haven't tested this by filling up my device literally 100%, so this is just an assumption.

 

Yes, raw system partitions are 10.94GB (not including those hidden, missing partitions) ARE HUGE for mobile OS. Just like Linus mensioned on WAN show, pixel devices takes up only about 6gigs and even has dual OS partition to seamless update/fallback OS. But on the other side, modern windows takes up about 16-20 gig on fresh install (depending on drivers) and skyrockets if you install pdf viewer, office, etc. I think that applies to macOS too. (Let's not talk about linux. They vary greatly. Though, I think I remember fresh ubuntu being under 10gig. don't quote me on that) Samsung's OS is full of features. Samsung even supports literally 'modding' your device to your likings with Good-Lock app. (Go try it on the Galaxy

 Store if you haven't. You have been wasting your Galaxy if you didn't use it.) They support Smart-Things or Find your device without installing a seperate app. Whether you like it or not, they have Bixby and Bixby routines included with your phone. You can't find these features on any other phones. At least not with this level of customization, build quality, and features.

There's no denying on that Samsung has a lot of bloat preinstalled and the fact that system image is HUGE. But In my opinion, this is justifiable. It just needs a little bit of diet.

 

Here is my spreadsheet:

https://docs.google.com/spreadsheets/d/14AlFARcdSbKqaMk8-ntRDCRTq8h7_6HH/edit?usp=sharing&ouid=100210223171289014815&rtpof=true&sd=true

Do note that my calculations are based on Korean varient of S21 (SM-G991N)

 

Note: 'changes eveytime' is not actually true. It actually changes 'time to time' but still I saw it change without any reasons. (no reboot, no update etc.)

[Sooneung]

Too tired to fix grammer nor the spreadsheet. Writing this at 5:30 AM in S. Korea. Please keep that in mind. thx!

[moatmote]

Good investigation here. I knew what was going on for the most part, but it's cool to see the numbers. This was actually only half the issue however. I cover it more in depth here, but the tl;dr is that a good number of people never gave My Files permission to read user app storage utilization, and Android bundles almost all unknown utilization into System, so many people were reading System utilization that was including ALL their user apps and respective caches.

3 hours ago, Sooneung said:

pixel devices takes up only about 6gigs and even has dual OS partition to seamless update/fallback OS.

Also, I mentioned this in my post, but no they don't because they use Virtual A/B now.

[Sooneung]

17 hours ago, moatmote said:

but no they don't because they use Virtual A/B now.

That's even better. I wonder why samsung wouldn't implement that. It's not like it takes more space. The 'Real A/B' takes a lot of space and considering that 64gb was standard for high end phones back in those days, I always thought it was really inefficient and wastful stuff to implement. Now that they have virtual a/b thing, it is kinda stupid for the manufacturers to not implement that feature.

[moatmote]

Also, I'm pretty sure Linus got that 6 GB figure for Pixel devices from the bullshit ArsTechnica article (which humorously mentions A/B as an argument for why Samsung is so much worse, but then almost instantly goes on to debunk itself by mentioning Virtual A/B). Most of the screenshots I've seen for Pixel devices place it closer to 10-20 GB

 

They made an update that still has misinformation though. Note the second paragraph.

Quote

Update: The original version of this article glossed over the fact that Android's storage screen starts with the advertised storage space, not the actual storage space, and then fudges the "system" numbers to make everything add up. Therefore it's not fair to compare Android to Windows or to compare phones of differing storage sizes. The 60GB number is from a 512GB Galaxy S23 device. Last year the number was around 49GB on a Galaxy S22 512GB phone, so the 512GB version, including all the same inaccurate storage calculations, somehow jumped 10GB year over year.

 

We can calculate the real world GB usage, and while all the numbers get smaller, the relative distance between Google and Samsung does not change. A 128GB Pixel actually has only 119GB of actual storage, so it erroneously adds 9GB to the "15GB" system on a 128GB phone, for an actual size of 6GB. A 512GB phone has 477GB of actual storage, so Samsung's 60GB storage size is 25GB on a 512GB phone, where last year it was 15GB. Samsung's 25GB Android package is still bigger than ever and four times the size of Google's 6GB Android install.

 

I don't want to retype this so I'll just copy my comments on that article:

Quote

Actually, I realized I made a mistake earlier. Many vendors add the "missing" storage from GB to GiB conversion, but some don't. Notably Pixel devices don't do this. The evidence? There are multiple screenshots in that same Twitter thread of Pixel phones that have reported System sizes under or near JUST the size of that difference, leaving little to no System storage for the actual OS, were you to subtract it.

 

Here are the "conversion correction" sizes for each storage tier:

• 128 GB: 8.79 GB
• 256 GB: 17.58 GB
• 512 GB: 35.16 GB

Now note the following screenshots:

Look at all these amazing Pixel phones with negative gigabyte operating systems!

 

Of course, this means that this update is completely bullshit.

 

 

As you can see, the measured System sizes for these Pixel devices make it impossible for them to be doing the same compensating as Samsung and some other vendors, so the gap between them is even smaller.

 

One other thing. Your changing reported System size, could it be related to RAM Plus, or have you disabled that? 

 

 

[E-waste]

Regardless of all this, every android user all three billion of us, should be using a firewall to block Google AND Samsung server connections.  I don't know what they are for and we will probably never be told by them what they collect.  Because of thos opaqueness on top of an "open-aource" system, block it all.

 

I recommend RethinkDNS.  I'm not a part of the dev or marketing team, I choose to share this one because it's open-source, available on F-droid and the background tech experience of the devs including working for Amazon and other large tech jobs.  The devs know exactly what's going on and truly want to buold the tools you can use to block all this tracking.