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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connOptions.uiInterface = &uiInterface;
    connOptions.m_banman = node.banman.get();
    connOptions.m_msgproc = node.peerman.get();
    connOptions.nSendBufferMaxSize = 1000 * args.GetArg("-maxsendbuffer", DEFAULT_MAXSENDBUFFER);
    connOptions.nReceiveFloodSize = 1000 * args.GetArg("-maxreceivebuffer", DEFAULT_MAXRECEIVEBUFFER);
    connOptions.m_added_nodes = args.GetArgs("-addnode");
    connOptions.nMaxOutboundLimit = 1024 * 1024 * args.GetArg("-maxuploadtarget", DEFAULT_MAX_UPLOAD_TARGET);
    connOptions.m_peer_connect_timeout = peer_connect_timeout;
    for (const std::string& bind_arg : args.GetArgs("-bind")) {
        CService bind_addr;
        const size_t index = bind_arg.rfind('=');
        if (index == std::string::npos) {
            if (Lookup(bind_arg, bind_addr, GetListenPort(), false)) {
                connOptions.vBinds.push_back(bind_addr);
                continue;
            }
        } else {
            const std::string network_type = bind_arg.substr(index + 1);
            if (network_type == "onion") {
                const std::string truncated_bind_arg = bind_arg.substr(0, index);
                if (Lookup(truncated_bind_arg, bind_addr, BaseParams().OnionServiceTargetPort(), false)) {
                    connOptions.onion_binds.push_back(bind_addr);
                    continue;
                }
            }
        }
        return InitError(ResolveErrMsg("bind", bind_arg));
    }
    if (connOptions.onion_binds.empty()) {
        connOptions.onion_binds.push_back(DefaultOnionServiceTarget());