679a413f11
Summary: Delete database instances to make sure there are no loose threads running before exit(). This fixes segfaults seen when running workloads through CompositeEnvs with custom file systems. For further background on the issues arising when using CompositeEnvs, see the discussion in: https://github.com/facebook/rocksdb/pull/6878 Pull Request resolved: https://github.com/facebook/rocksdb/pull/7327 Reviewed By: cheng-chang Differential Revision: D23433244 Pulled By: ajkr fbshipit-source-id: 4e19cf2067e3fe68c2a3fe1823f24b4091336bbe