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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else
            return InitError(ResolveErrMsg("externalip", strAddr));
    }
    
    if (args.IsArgSet("-asmap")) {
        fs::path asmap_path = fs::path(args.GetArg("-asmap", ""));
        if (asmap_path.empty()) {
            asmap_path = DEFAULT_ASMAP_FILENAME;
        }
        if (!asmap_path.is_absolute()) {
            asmap_path = gArgs.GetDataDirNet() / asmap_path;
        }
        if (!fs::exists(asmap_path)) {
            InitError(strprintf(_("Could not find asmap file %s"), asmap_path));
            return false;
        }
        std::vector<bool> asmap = CAddrMan::DecodeAsmap(asmap_path);
        if (asmap.size() == 0) {
            InitError(strprintf(_("Could not parse asmap file %s"), asmap_path));
            return false;
        }
        const uint256 asmap_version = SerializeHash(asmap);
        node.connman->SetAsmap(std::move(asmap));
        LogPrintf("Using asmap version %s for IP bucketing\n", asmap_version.ToString());
    } else {
        LogPrintf("Using /16 prefix for IP bucketing\n");
    }
#if ENABLE_ZMQ
    g_zmq_notification_interface = CZMQNotificationInterface::Create();
    if (g_zmq_notification_interface) {