fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph

解轶伦 39fcaf8246 delete superversions in BackgroundCallPurge (#6146 An error occurred ) ... Summary: I found that CleanupSuperVersion() may block Get() for 30ms+ （per MemTable is 256MB）. Then I found "delete sv" in ~SuperVersion() takes the time. The backtrace looks like this DBImpl::GetImpl() -> DBImpl::ReturnAndCleanupSuperVersion() -> DBImpl::CleanupSuperVersion() : delete sv; -> ~SuperVersion() I think it's better to delete in a background thread, please review it。 Pull Request resolved: https://github.com/facebook/rocksdb/pull/6146 Differential Revision: D18972066 fbshipit-source-id: 0f7b0b70b9bb1e27ad6fc1c8a408fbbf237ae08c		5 years ago
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rocksdb	delete superversions in BackgroundCallPurge (#6146 An error occurred )	5 years ago