add locks while accessing redolog internal maps

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 71.18%. Comparing base (0eff36f) to head (8c58b16). Report is 1 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #366 +/- ## ========================================== - Coverage 71.21% 71.18% -0.04% ========================================== Files 178 178 Lines 23633 23635 +2 ========================================== - Hits 16831 16825 -6 - Misses 5465 5471 +6 - Partials 1337 1339 +2 ```

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