1910560c2c
Summary: The bug fixed in https://github.com/facebook/rocksdb/pull/1816/ is now applicable to iterator too. This was not an issue but https://github.com/facebook/rocksdb/pull/2886 caused the regression. If a put and DB flush happens just between iterator to get latest sequence number and getting super version, empty result for the key or an older value can be returned, which is wrong. Fix it in the same way as the fix in https://github.com/facebook/rocksdb/issues/1816, that is to get the sequence number after referencing the super version. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6973 Test Plan: Will run stress tests for a while to make sure there is no general regression. Reviewed By: ajkr Differential Revision: D22029348 fbshipit-source-id: 94390f93630906796d6e2fec321f44a920953fd1