Summary:
Context:
While all the non-trivial write operations in BackupEngine go through the RateLimiter, reads currently do not. In general, this is not a huge issue because (especially since some I/O efficiency fixes) reads in BackupEngine are mostly limited by corresponding writes, for both backup and restore. But in principle we should charge the RateLimiter for reads as well.
- Charged read operations in `BackupEngineImpl::CopyOrCreateFile`, `BackupEngineImpl::ReadFileAndComputeChecksum`, `BackupEngineImpl::BackupMeta::LoadFromFile` and `BackupEngineImpl::GetFileDbIdentities`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8722
Test Plan:
- Passed existing tests
- Passed added unit tests
Reviewed By: pdillinger
Differential Revision: D30610464
Pulled By: hx235
fbshipit-source-id: 9b08c9387159a5385c8d390d6666377a0d0117e5
45175ca2e1