This change adds a new option to the REST api and correspondingly, to scylla nodetool: use_sstable_identifier.
When set, we use the sstable identifier, if available, to name each sstable in the snapshots directory
and the manifest.json file, rather than using the sstable generation.
This can be used by the user (e.g. Scylla Manager) for global deduplication with tablets, where an sstable
may be migrated across shards or across nodes, and in this case, its generation may change, but its
sstable identifier remains sstable.
Currently, Scylla manager uses the sstable generation to detect sstables that are already backed up to
object storage and exist in previous backed up snapshots.
Historically, the sstable generation was guaranteed to be unique only per table per node,
so the dedup code currently checks for deduplication in the node scope.
However, with tablet migration, sstables are renamed when migrated to a different shard,
i.e. their generation changes, and they may be renamed when migrated to another node,
but even if they are not, the dedup logic still assumes uniqueness only within a node.
To address both cases, we keep the sstable_id stable throughout the sstable life cycle (since 3a12ad96c7).
Given the globally unique sstable identifier, scylla manager can now detect duplicate sstables
in a wider scope. This can be cluster-wide, but we practically need only rack-wide deduplication
or dc-wide, as tablets are migrated across racks only in rare occasions (like when converting from a
numerical replication factor to a rack list containing a subset of the available racks in a datacenter).
Fixes#27181
* New feature, no backport required
Closesscylladb/scylladb#27184
* github.com:scylladb/scylladb:
database: truncate_table_on_all_shards: set use_sstable_identifier to true
nodetool: snapshot: add --use-sstable-identifier option
api: storage_service: take_snapshot: add use_sstable_identifier option
test: database_test: add snapshot_use_sstable_identifier_works
test: database_test: snapshot_works: add validate_manifest
sstable: write_scylla_metadata: add random_sstable_identifier error injection
table: snapshot_on_all_shards: take snapshot_options
sstable: add get_format getter
sstable: snapshot: add use_sstable_identifier option
db: snapshot_ctl: snapshot_options: add use_sstable_identifier options
db: snapshot_ctl: move skip_flush to struct snapshot_options
8192f45e84