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, "%s: sending inv peer=%d hash=%s\n", __func__,
                            pto->GetId(), hashToAnnounce.ToString());
                    }
                }
            }
            peer->m_blocks_for_headers_relay.clear();
        }
        
        
        
        std::vector<CInv> vInv;
        {
            LOCK(peer->m_block_inv_mutex);
            vInv.reserve(std::max<size_t>(peer->m_blocks_for_inv_relay.size(), INVENTORY_BROADCAST_MAX));
            
            for (const uint256& hash : peer->m_blocks_for_inv_relay) {
                vInv.push_back(CInv(MSG_BLOCK, hash));
                if (vInv.size() == MAX_INV_SZ) {
                    m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));
                    vInv.clear();
                }
            }
            peer->m_blocks_for_inv_relay.clear();
        }
        if (pto->m_tx_relay != nullptr) {
                LOCK(pto->m_tx_relay->cs_tx_inventory);
                
                bool fSendTrickle = pto->HasPermission(NetPermissionFlags::NoBan);
                if (pto->m_tx_relay->nNextInvSend < current_time) {
                    fSendTrickle = true;