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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StopTorControl();
    
    
    if (node.scheduler) node.scheduler->stop();
    if (node.chainman && node.chainman->m_load_block.joinable()) node.chainman->m_load_block.join();
    StopScriptCheckWorkerThreads();
    
    
    node.peerman.reset();
    node.connman.reset();
    node.banman.reset();
    node.addrman.reset();
    if (node.mempool && node.mempool->IsLoaded() && node.args->GetArg("-persistmempool", DEFAULT_PERSIST_MEMPOOL)) {
        DumpMempool(*node.mempool);
    }
    
    if (node.fee_estimator) node.fee_estimator->Flush();
    
    if (node.chainman) {
        LOCK(cs_main);
        for (CChainState* chainstate : node.chainman->GetAll()) {
            if (chainstate->CanFlushToDisk()) {
                chainstate->ForceFlushStateToDisk();
            }
        }
    }
    
    
    GetMainSignals().FlushBackgroundCallbacks();