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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{
        return m_coins_views->m_catcherview;
    }
    
    void ResetCoinsViews() { m_coins_views.reset(); }
    
    size_t m_coinsdb_cache_size_bytes{0};
    
    size_t m_coinstip_cache_size_bytes{0};
    
    
    bool ResizeCoinsCaches(size_t coinstip_size, size_t coinsdb_size)
        EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
    
    void LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, FlatFilePos* dbp = nullptr);
    /**
     * Update the on-disk chain state.
     * The caches and indexes are flushed depending on the mode we're called with
     * if they're too large, if it's been a while since the last write,
     * or always and in all cases if we're in prune mode and are deleting files.
     *
     * If FlushStateMode::NONE is used, then FlushStateToDisk(...) won't do anything
     * besides checking if we need to prune.
     *
     * @returns true unless a system error occurred
     */
    bool FlushStateToDisk(
        const CChainParams& chainparams,