List<ColumnKey> keysConsumedOrWhatever = new ArrayList<>();
        Iterator<ColumnKey> iterator = queuedColumns.keySet().iterator();
        while(iterator.hasNext() && keysConsumedOrWhatever.size() < 1000) {
            ColumnKey key = iterator.next();
            Column c = queuedColumns.get(key);
            if (c != null && canRegen(c.lastChanged)) {
                keysConsumedOrWhatever.add(key);
            }
            queuedColumns.remove(key);
        }