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My university's cubesat team is looking for a Linux filesystem that will be resistant to bitrot in the unshielded radiation of outer space.

We have 3 flash-based drives but only need the storage of one. My first thought was ZFS in RaidZ1, but I'm not sure if that works with only 3 drives.

The CPU is using an ARM architecture.

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    I have no experience with radioactive environment, but ext4(3)+raid1 is the safest. zfs has too much overhead for an embedded device. aaand...if it's flash, you have to look at f2fs: kernel.org/doc/Documentation/filesystems/f2fs.txt – Ipor Sircer Aug 30 '16 at 0:53
  • Should probably look into BTRFS since it has checksums on data and transparent recovery of files. If you have three legs of a btrfs raid mirror that might make it more resilient to bit rot. – Bratchley Aug 30 '16 at 1:22
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    Resilient hardware in a leaden box...? Do we know what the failure modes for flash chips are in radiation? Single bits flipping by the dozen, whole chips going dumb and dying perhaps? The controller/CPU might have problems too. – ilkkachu Aug 30 '16 at 8:41
  • Yes, it's going up in a CubeSat, which is approximately 30cm by 10cm by 10cm. I don't know the exact chip models, but I do know that the 3 EMMC chips we use have 512MB of ECC RAM. I was hoping to build the resiliency into the filesystem so that the potentially faulty hardware could be held up by a good underlying FS layout. – ijustlovemath Sep 6 '16 at 20:26