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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{
    {
        LOCK(cs_main);
        CNodeState* state = State(nodeid);
        if (state == nullptr)
            return false;
        stats.nSyncHeight = state->pindexBestKnownBlock ? state->pindexBestKnownBlock->nHeight : -1;
        stats.nCommonHeight = state->pindexLastCommonBlock ? state->pindexLastCommonBlock->nHeight : -1;
        for (const QueuedBlock& queue : state->vBlocksInFlight) {
            if (queue.pindex)
                stats.vHeightInFlight.push_back(queue.pindex->nHeight);
        }
    }
    PeerRef peer = GetPeerRef(nodeid);
    if (peer == nullptr) return false;
    stats.m_starting_height = peer->m_starting_height;
    
    
    
    
    
    
    std::chrono::microseconds ping_wait{0};
    if ((0 != peer->m_ping_nonce_sent) && (0 != peer->m_ping_start.load().count())) {
        ping_wait = GetTime<std::chrono::microseconds>() - peer->m_ping_start.load();
    }
    stats.m_ping_wait = ping_wait;
    return true;
}
void PeerManagerImpl::AddToCompactExtraTransactions(const CTransactionRef& tx)