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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Unload();
    }
};
/**
 * A convenience class for constructing the CCoinsView* hierarchy used
 * to facilitate access to the UTXO set.
 *
 * This class consists of an arrangement of layered CCoinsView objects,
 * preferring to store and retrieve coins in memory via `m_cacheview` but
 * ultimately falling back on cache misses to the canonical store of UTXOs on
 * disk, `m_dbview`.
 */
class CoinsViews {