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Tip about profiles of metadata block groups :

By default the BTRFS partition on the Jolla 1 phone uses "dup" profile for the metadata block groups.

i.e.: BTRFS will keep 2 copies of each metadata block group.

According to the mkfs.btrfs manpage, this isn't recommended on SSD anymore.

(e.g.: the flash translation layer / wear-leveling of flash media will very likely group the writes together, which will cause both dup copies to end up on the same erase-block. If the flash goes bust, both copies will very likely end-up lost at the same time, negating any benefit of dup profiles on flash media, as opposed to rotational media)

I would suggest switching the pofile :

devel-su
btrfs balance -v -f -mconvert=single /

This will reduce the amount of space allocated on metadata block groups by half, which will reduce a bit the pressure on the free-space / the partition full problems that users report.

I've personally used my smartphone (both eMMC and uSDHC card) this way for over 1 year without any problem to report (Including going through SailfishOS updates, surviving crashes, etc.)

Tip about profiles of metadata block groups :

By default the BTRFS partition on the Jolla 1 phone uses "dup" profile for the metadata block groups.

i.e.: BTRFS will keep 2 copies of each metadata block group.

According to the mkfs.btrfs manpage, this isn't recommended on SSD anymore.

(e.g.: the flash translation layer / wear-leveling of flash media will very likely group the writes together, which will cause both dup copies to end up on the same erase-block. If the flash goes bust, both copies will very likely end-up lost at the same time, negating any benefit of dup profiles on flash media, as opposed to rotational media)

I would suggest switching the pofile :

devel-su
btrfs balance start -v -f -mconvert=single /

This will reduce the amount of space allocated on metadata block groups by half, which will reduce a bit the pressure on the free-space / the partition full problems that users report.

I've personally used my smartphone (both eMMC and uSDHC card) this way for over 1 year without any problem to report (Including going through SailfishOS updates, surviving crashes, etc.)

Tip about profiles of metadata block groups :

By default the BTRFS partition on the Jolla 1 phone uses "dup" profile for the metadata block groups.

i.e.: BTRFS will keep 2 copies of each metadata block group.

According to the mkfs.btrfs manpage, this isn't recommended on SSD anymore.

(e.g.: the flash translation layer / wear-leveling of flash media will very likely group the writes together, which will cause both dup copies to end up on the same erase-block. If the flash goes bust, both copies will very likely end-up lost at the same time, negating any benefit of dup profiles on flash media, as opposed to rotational media)

I would suggest switching the pofile :

devel-su
btrfs balance start -v -f -mconvert=single /

This will reduce the amount of space allocated on metadata block groups by half, which will reduce a bit the pressure on the free-space / the partition full problems that users report.

I've personally used my smartphone (both eMMC and uSDHC card) this way for over 1 year without any problem to report (Including going through SailfishOS updates, surviving crashes, etc.)