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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LogPrint(BCLog::NET, "non-version message before version handshake. Message \"%s\" from peer=%d\n", SanitizeString(msg_type), pfrom.GetId());
        return;
    }
    
    const CNetMsgMaker msgMaker(pfrom.GetCommonVersion());
    if (msg_type == NetMsgType::VERACK) {
        if (pfrom.fSuccessfullyConnected) {
            LogPrint(BCLog::NET, "ignoring redundant verack message from peer=%d\n", pfrom.GetId());
            return;
        }
        if (!pfrom.IsInboundConn()) {
            LogPrintf("New outbound peer connected: version: %d, blocks=%d, peer=%d%s (%s)\n",
                      pfrom.nVersion.load(), peer->m_starting_height,
                      pfrom.GetId(), (fLogIPs ? strprintf(", peeraddr=%s", pfrom.addr.ToString()) : ""),
                      pfrom.ConnectionTypeAsString());
        }
        if (pfrom.GetCommonVersion() >= SENDHEADERS_VERSION) {
            
            
            
            
            m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::SENDHEADERS));
        }
        if (pfrom.GetCommonVersion() >= SHORT_IDS_BLOCKS_VERSION) {