[Poll] File System(s) support on SD card for Jolla Tablet

That's conditional on the MS license allowing optional support for FAT in devices though. They may not.

FAT should not be a problem, it is a very old filesystem and the patents should have expired. The latest claims survived were about long filenames, but the Linux filesystem changed the encoding enough to be in the clear (at least, that part was changed, it is difficult to say for sure, since patent wars happen behind closed doors)

Let us try to make the best of the situation, and ask for some useful functionality in the mass memory department. We will probably get both, in the end, if Jolla survives long enough to deliver it. :)

Which it might not do, if it continues misunderstanding its own userbase, but...

Anyway, let us keep on topic:

File System(s) support on SD card for Jolla Tablet

This question does not address it.

I just sad I want every format that's free

If the Jolla device supported UDF, it might start some interest in it as a format for all removable media. Honestly, I think the only reason it isn't used more is because it's not supported by the Windows Format UI. It's fully supported by the rest of Windows though. Even the Format command!

In fact on my windows pc I have set up a batch file which asks for the drive letter in an inputbox and formats to UDF, really simple. And I have verified a few minutes ago that my 32 GB microsd card formatted to UDF on windows 7 works perfectly on the latest ubuntu, both read and write.

And please add UDF support to the Jolla phone too!

I'm new to this board (TJC), but I have a suspect that if an answer was preceded by many others, its visibility is poor to start with, and doesn't really get the chance to get better. May be that my answer is worse than others, but in such case it would be nice to know why. I tested this evening a UDF hard drive partition of 300 GB, was perfectly read and written by both Ubuntu and Windows 8. Sounds to me like a great filesystem for cross compatibility between Sailfish and PCs?

Adding this link here as it is related, please upvote: https://together.jolla.com/question/10353/support-udf-for-microsd-filesystem/

Do you want to marry me? ;)

fyi, btrfs is the standard fs for Jolla internal flash...

@chemist: I am already in a happy relationship. :) @dac: Thought so, still, people are asking for it. I somehow took it for granted that Sailfish will read any major linux fs on a sdcard. At least I expected that you could instal xfs/jfs/reiserX with the package management tool.

"Every possible linux filesystem" is too much to ask.

Of course, it does not cost much to add the relative modules, but "supporting" them means that if there are bugs, Jolla employees will have fo analyze the problem and fix it. This is not optimal, since resources could be spent on rarely used features.

So let us focus on a small selection of options that would be useful to support, and make them work flawlessly.

I would say that:

• FAT is common and already supported, I do not think this is controversial
• btrfs is the filesystem used for the internal storage, supporting it on the SD card should not be a problem
• ext4 is stable and commonly supported in linux based devices, it could be an additional candidate.
• f2fs could be interesting, as it is supposed to be optimized for flash memory. I do not know much about it

Personally I would keep the choices to that. Business factors may require the support of exFat. Even because it probably has been promised as a perk for the 1.5M goal. Jolla is in a bad position on that account no matter what they do - they cannot really take that back, nor could they make free sources enthusiasts -- like myself -- completely happy.

Anyway, as long as it is easy to use a well supported Linux filesystem, I am happy.

This is the best answer yet IMHO. I strongly believe exFat should be an optional un/install (like in settings) as to not add proprietary blobs to those who don't want them. But you must think about interoperability. On should be able able to transfer data from the sdcard to, say, a computer without any hassle (someone mentioned KISS). As I see it, the best solution is to allow an easy way to transfer from the device (internal and external memory) through wifi/bt or ssh. I don't think is it fundamental to have an sdcard formated so it can be read by every computer, Jolla will not be able to please everybody anyway (win/mac users need sth lile exFat and unix users want os fs). But we need some way to transfer datas between devices. If I want to put photos/videos on my tablet, I must be able to do it easily, am I using a mac, windows or unix. So some compromise has to be found here. Camera compatibility is not an issue since, as someone mentioned earlier, we don't see much camera support more than 32gb, nor users buy more than that (the need is not real).

So a good idea would indeed be to support all major opensource fs, an optional exFat support and a wireless transfer sytem (although one can buy one of those wifi sdcards, even though I don't know if they work well). And encryption support, which would be a huge bonus.

The "about device" could show how big (and what type of) SDxx cards are supported, based on whether the additional package is installed or not. It's good for users to have an easy way to check it imo.

xfs is good only on systems with robust UPS and those that almost never get switched off. If you remove your xfs formatted sdcard without umouting it you'll lose data. fsck.xfs will repair the file system but your data is gone! I dealt with xfs on my personal desktop for few years and despite i had a UPS i did lose data few times. xfs journaling will kill sdcard rather quick, that's why sdcards are formated always with nonjournaling fs or journaling switched off. Xfs without journaling is pointless. ;)

@Kollin I rember reading somewhere that power loss used to indeed be quite an issue with XFS, but supposedly should be fixed in recent XFS versions. Unfortunately I have not been able to find the article now...

As for Journaling, that might indeed be a good point. It could produce a lot of small writes and if I remember correctly, writes on flash devices need to be done in fairly large sectors, so that can mean quite a lot of sectors being used up even though the data amount is quite small.

On the other hand, on a 128 GB micro SD card, there could be a lot of sectors and in many cases writing could be quite sporadically (photos/videos from camera, dumping music/video files).

I think some sort of a benchmark of all the different filesystems would be really nice! :) Especially if the level of "wear" for a given filesystem could be measured somehow (eq. amount of wear for 10000 128 kB files, for 10 1 GB files, etc. :) ).

I don't know how but btrfs killed two of my 64gb sdxc cards (mind that btrfs is optimized to work with flash drives). xfs is just not designed for flash drives, i'm may be wrong but i had my bad experience with it. As a long time linux user i have my share of fs hacking (ext2 reiserfs xfs reiser4 btrfs ext4...) witch points me toward the decision that next sdxc card will be formatted with ext4. Tuned ext4

Supporting XFS has nothing to do with being limited to use SD cards. Imagine you attach an external hard drive over USB which has an XFS partition.

One word: http://en.wikipedia.org/wiki/USB_Attached_SCSI

@javispedro Well UASP actually makes sense - #unlike iSCSI. ;-)

This is all I ever use and is always supported on all Linux distributions i have ever used (ext4 since it came and ext3 before that).