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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* Bitcoin protocol messages
* Bitcoin Core P2P design
* Running our unit and functional tests

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public:
    
    
    CCoinsViewDB m_dbview GUARDED_BY(cs_main);
    
    CCoinsViewErrorCatcher m_catcherview GUARDED_BY(cs_main);
    
    
    std::unique_ptr<CCoinsViewCache> m_cacheview GUARDED_BY(cs_main);
    
    
    
    
    
    
    CoinsViews(std::string ldb_name, size_t cache_size_bytes, bool in_memory, bool should_wipe);
    
    void InitCache() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
};
enum class CoinsCacheSizeState