"
Today, if scylla crashes mid-way in sstable::idempotent-move-sstable
or sstable::create_links we may end up in an inconsistent state
where it refuses to restart due to the presence of the moved-
sstable component files in both the staging directory and
main directory.
This series hardens scylla against this scenario by:
1. Improving sstable::create_links to identify the replay condition
and support it.
2. Modifying the algorithm for moving sstables between directories
to never be in a state where we have two valid sstable with the
same generation, in both the source and destination directories.
Instead, it uses the temporary TOC file as a marker for rolling
backwards or forewards, and renames it atomically from the
destination directory back to the source directory as a commit
point. Before which it is preparing the sstable in the destination
dir, and after which it starts the process of deleting the sstable
in the source dir.
Fixes#7429
Refs #5714
"
* tag 'idempotent-move-sstable-v3' of github.com:bhalevy/scylla:
sstable: create_links: support for move
sstable_directory: support sstables with both TemporaryTOC and TOC
sstable: create_links: move automatic sstring variables
sstable: create_links: use captured comps
sstable: create_links: capture dir by reference
sstable: create_links: fix indentation
sstable: create_links: no need to roll-back on failure anymore
sstable: create_links: support idempotent replay
sstable: create_links: cleanup style
sstable: create_links: add debug/trace logging
sstable: move_to_new_dir: rm TOC last
sstable: move_to_new_dir: io check remove calls
test: add sstable_move_test
5b312a1238