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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LogPrintf("%s\n", e.what());
                strLoadError = _("Error opening block database");
                failed_verification = true;
                break;
            }
            if (!failed_verification) {
                fLoaded = true;
                LogPrintf(" block index %15dms\n", GetTimeMillis() - load_block_index_start_time);
            }
        } while(false);
        if (!fLoaded && !ShutdownRequested()) {
             f
            if (!fReset) {
                bool fRet = uiInterface.ThreadSafeQuestion(
                    strLoadError + Untranslated(".\n\n") + _("Do you want to rebuild the block database now?"),
                    strLoadError.original + ".\nPlease restart with -reindex or -reindex-chainstate to recover.",
                    "", CClientUIInterface::MSG_ERROR | CClientUIInterface::BTN_ABORT);
                if (fRet) {
                    fReindex = true;
                    AbortShutdown();
                } else {
                    LogPrintf("Aborted block database rebuild. Exiting.\n");
                    return false;
                }
            } else {
                return InitError(strLoadError);
            }
        }
    }
     A