Previously, during backup, SSTable components are preserved in the
snapshot directory even after being uploaded. This leads to redundant
uploads in case of failed backups or restarts, wasting time and
resources (S3 API calls).
This change removes SSTable components from the snapshot directory once
they are successfully uploaded to the target location. This prevents
re-uploading the same files and reduces disk usage.
This change only "Refs" https://github.com/scylladb/scylladb/issues/20655, because, we can further optimize
the backup process, consider:
- Sending HEAD requests to S3 to check for existing files before uploading.
- Implementing support for resuming partially uploaded files.
Fixes https://github.com/scylladb/scylladb/issues/21799
Refs https://github.com/scylladb/scylladb/issues/20655
---
the backup API is not used in production yet, so no need to backport.
Closesscylladb/scylladb#22285
* github.com:scylladb/scylladb:
backup_task: remove a component once it is uploaded
backup_task: extract component upload logic into dedicated function
snapshot-ctl: change snapshot_ctl::run_snapshot_modify_operation() to regular func
4d8d7f1f1d