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(peer->m_getdata_requests_mutex);
            peer->m_getdata_requests.insert(peer->m_getdata_requests.end(), vInv.begin(), vInv.end());
            ProcessGetData(pfrom, *peer, interruptMsgProc);
        }
        return;
    }
    if (msg_type == NetMsgType::GETBLOCKS) {
        CBlockLocator locator;
        uint256 hashStop;
        vRecv >> locator >> hashStop;
        if (locator.vHave.size() > MAX_LOCATOR_SZ) {
            LogPrint(BCLog::NET, "getblocks locator size %lld > %d, disconnect peer=%d\n", locator.vHave.size(), MAX_LOCATOR_SZ, pfrom.GetId());
            pfrom.fDisconnect = true;
            return;
        }
        
        
        
        
        
        
        
        {
            std::shared_ptr<const CBlock> a_recent_block;
            {
                LOCK(cs_most_recent_block);
                a_recent_block = most_recent_block;
            }
            BlockValidationState state;
            if (!m_chainman.ActiveChainstate().ActivateBestChain(state, m_chainparams, a_recent_block)) {