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(m_peer_mutex);
    for(auto& it : m_peer_map) it.second->m_ping_queued = true;
}
void PeerManagerImpl::RelayTransaction(const uint256& txid, const uint256& wtxid)
{
    WITH_LOCK(cs_main, _RelayTransaction(txid, wtxid););
}
void PeerManagerImpl::_RelayTransaction(const uint256& txid, const uint256& wtxid)
{
    m_connman.ForEachNode([&txid, &wtxid](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
        AssertLockHeld(::cs_main);
        CNodeState* state = State(pnode->GetId());
        if (state == nullptr) return;
        if (state->m_wtxid_relay) {
            pnode->PushTxInventory(wtxid);
        } else {
            pnode->PushTxInventory(txid);
        }
    });
}
void PeerManagerImpl::RelayAddress(NodeId originator,
                                   const CAddress& addr,
                                   bool fReachable)
{