There are some potential feefilter cleanups mentioned and motivated in comment https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-805808485 . If you address the locking one, please be careful and make sure that `round()` is only called under a lock. See https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-807992199

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int64_t m_total_coinsdb_cache{0};
    
    
    
    
    
    
    
    CChainState& InitializeChainstate(CTxMemPool& mempool, const std::optional<uint256>& snapshot_blockhash = std::nullopt)
        EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
    
    std::vector<CChainState*> GetAll();
    
    
    
    
    
    
    
    
    
    
    
    
    
    [[nodiscard]] bool ActivateSnapshot(
        CAutoFile& coins_file, const SnapshotMetadata& metadata, bool in_memory);
    
    CChainState& ActiveChainstate() const;
    CChain& ActiveChain() const { return ActiveChainstate().m_chain; }