5b4c709fad
Summary: Adds a DB option `atomic_flush` to control whether to enable this feature. This PR is a subset of [PR 3752](https://github.com/facebook/rocksdb/pull/3752). Pull Request resolved: https://github.com/facebook/rocksdb/pull/4023 Differential Revision: D8518381 Pulled By: riversand963 fbshipit-source-id: 1e3bb33e99bb102876a31b378d93b0138ff6634f