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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}
    nConnectTimeout = args.GetArg("-timeout", DEFAULT_CONNECT_TIMEOUT);
    if (nConnectTimeout <= 0) {
        nConnectTimeout = DEFAULT_CONNECT_TIMEOUT;
    }
    peer_connect_timeout = args.GetArg("-peertimeout", DEFAULT_PEER_CONNECT_TIMEOUT);
    if (peer_connect_timeout <= 0) {
        return InitError(Untranslated("peertimeout cannot be configured with a negative value."));
    }
    if (args.IsArgSet("-minrelaytxfee")) {
        CAmount n = 0;
        if (!ParseMoney(args.GetArg("-minrelaytxfee", ""), n)) {
            return InitError(AmountErrMsg("minrelaytxfee", args.GetArg("-minrelaytxfee", "")));
        }
        
        ::minRelayTxFee = CFeeRate(n);
    } else if (incrementalRelayFee > ::minRelayTxFee) {
        
        ::minRelayTxFee = incrementalRelayFee;
        LogPrintf("Increasing minrelaytxfee to %s to match incrementalrelayfee\n",::minRelayTxFee.ToString());
    }
    
    
    if (args.IsArgSet("-blockmintxfee")) {
        CAmount n = 0;
        if (!ParseMoney(args.GetArg("-blockmintxfee", ""), n))
            return InitError(AmountErrMsg("blockmintxfee", args.GetArg("-blockmintxfee", "")));
    }