Hello,

On 2021-01-06 T 18:56 +0300 Matwey V. Kornilov wrote:

> I have a question on JeOS images being built for ARM boards. I
> suppose that we agree that most target SBCs use microSD cards to
> store and run the OS. There are exceptions though.
>
> Currently, half of JeOS images are supplied with ext4 and the other
> half - btrfs.

I think, this is based on personal choice of the person who creates
the images...

> And frankly speaking, I cannot figure out the rule why
> some specific board receives JeOS with ext4 instead of btrfs or
> vice-versa.  I suppose this was related somehow to btrfs support in
> u-boot, right?

Some historic background on the SUSE Linux Enterprise side (from
around 2016): one of the reasons to use btrfs for microSD cards for
SLES on RPi3 was that, combined with compression on the filesystem
level, the number of IOPS needed is reduced, and booting (and other IO
related activities) speeds up, as the cost of (de)compression is lower
than the IO latency.

So long -
        MgE

> Another consideration. Does anybody know any research on what FS is
> the most friendly to SD cards?

--
Matthias G. Eckermann,    Director Product Management Linux Platforms
SUSE Software Solutions Germany GmbH - Maxfeldstr. 5 - 90409 Nürnberg
(HRB 36809, AG Nürnberg)           Geschäftsführer: Felix Imendörffer