Hi Kai, I never used that, but please take a look at F2FS too. BR, Alan On 7/18/23, Kai Tomerius <kai@xxxxxxxxxxx> wrote: > Hi Alan, > > thx a lot. > > I should have mentioned that I'll have a large NAND flash, so ext4 > might still be the file system of choice. The other ones you mentioned > are interesting to consider, but seem to be more fitting for a smaller > NOR flash. > > Regards > Kai > > > > On Mon, Jul 17, 2023 at 10:50:50AM -0300, Alan C. Assis wrote: >> Hi Kai, >> >> On 7/17/23, Kai Tomerius <kai@xxxxxxxxxxx> wrote: >> > Hi, >> > >> > let's suppose an embedded system with a read-only squashfs root file >> > system, and a writable ext4 data partition with data=journal. >> > Furthermore, the data partition shall be protected with dm-integrity. >> > >> > Normally, I'd umount the data partition while shutting down the >> > system. There might be cases though where power is cut. In such a >> > case, there'll be ext4 recoveries, which is ok. >> > >> > How robust would such a setup be? Are there chances that the ext4 >> > requires a fsck? What might happen if fsck is not run, ever? Is there >> > a chance that the data partition can't be mounted at all? How often >> > might that happen? >> > >> >> Please take a look at this document: >> >> https://elinux.org/images/0/02/Filesystem_Considerations_for_Embedded_Devices.pdf >> >> In general EXT4 is fine, but it has some limitation, more info here: >> https://opensource.com/article/18/4/ext4-filesystem >> >> I think Linux users suffer from the same problem we have with NuttX (a >> Linux-like RTOS): which FS to use? >> >> So for deep embedded systems running NuttX I follow this logic: >> >> I need better performance and wear leveling, but I don't need to worry >> about power loss: I choose SmartFS >> >> I need good performance, wear leveling and some power loss protection: >> SPIFFS >> >> I need good performance, wear leveling and good protection for >> frequent power loss: LittleFS >> >> In a NuttShell: There is no FS that 100% meets all user needs, select >> the FS that meets your core needs and do lots of field testing to >> confirm it works as expected. >> >> BR, >> >> Alan >
