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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}
    for (BlockFilterType filter_type : g_enabled_filter_types) {
        LogPrintf("* Using %.1f MiB for %s block filter index database\n",
                  filter_index_cache * (1.0 / 1024 / 1024), BlockFilterTypeName(filter_type));
    }
    LogPrintf("* Using %.1f MiB for chain state database\n", nCoinDBCache * (1.0 / 1024 / 1024));
    LogPrintf("* Using %.1f MiB for in-memory UTXO set (plus up to %.1f MiB of unused mempool space)\n", nCoinCacheUsage * (1.0 / 1024 / 1024), nMempoolSizeMax * (1.0 / 1024 / 1024));
    bool fLoaded = false;
    while (!fLoaded && !ShutdownRequested()) {
        const bool fReset = fReindex;
        auto is_coinsview_empty = [&](CChainState* chainstate) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {
            return fReset || fReindexChainState || chainstate->CoinsTip().GetBestBlock().IsNull();
        };
        bilingual_str strLoadError;
        uiInterface.InitMessage(_("Loading block index…").translated);
        do {
            const int64_t load_block_index_start_time = GetTimeMillis();
            try {
                LOCK(cs_main);
                chainman.InitializeChainstate(*Assert(node.mempool));
                chainman.m_total_coinstip_cache = nCoinCacheUsage;
                chainman.m_total_coinsdb_cache = nCoinDBCache;
                UnloadBlockIndex(node.mempool.get(), chainman);
                 
                 
                pblocktree.reset();
                pblocktree.reset(new CBlockTreeDB(nBlockTreeDBCache, false, fReset));
                if (fReset) {
                    pblocktree->WriteReindexing(true);