For some reasons when we delete a MergeTree Part in atomic way something may go wrong - and leave the `delete_tmp_*` folder or it's part on disk. This may lead to a disk space consumption over time.

It's suggested to delete this folders at least at server start-up. Current solution with `clearOldTemporaryDirectories()` doesn't work because this method is called periodically from a thread without any locks or advisory on folders - it may cause the race conditions.
else
    {
        {
            changeSettings(new_metadata.settings_changes, table_lock_holder);
            checkTTLExpressions(new_metadata, old_metadata);
            
            setProperties(new_metadata, old_metadata);
            DatabaseCatalog::instance().getDatabase(table_id.database_name)->alterTable(local_context, table_id, new_metadata);
            if (!maybe_mutation_commands.empty())
                mutation_version = startMutation(maybe_mutation_commands, local_context);
        }
        
        
        if (!maybe_mutation_commands.empty())
            waitForMutation(mutation_version);
    }
    {
        
        auto new_storage_settings = getSettings();
        if (old_storage_settings->non_replicated_deduplication_window != new_storage_settings->non_replicated_deduplication_window)
        {
            
            
            if (new_storage_settings->non_replicated_deduplication_window != 0 && format_version < MERGE_TREE_DATA_MIN_FORMAT_VERSION_WITH_CUSTOM_PARTITIONING)
                throw Exception("Deduplication for non-replicated MergeTree in old syntax is not supported", ErrorCodes::BAD_ARGUMENTS);
            deduplication_log->setDeduplicationWindowSize(new_storage_settings->non_replicated_deduplication_window);
        }
    }
}
CurrentlyMergingPartsTagger::CurrentlyMergingPartsTagger(