def make_figure_memory(extractors, what):
    """
    $ oq plot 'memory?'
    """
    import matplotlib.pyplot as plt
    [ex] = extractors
    task_info = ex.get('task_info').to_dict()
    fig, ax = plt.subplots()
    ax.grid(True)
    ax.set_xlabel('tasks')
    ax.set_ylabel('GB')
    start = 0
    for task_name in task_info:
        mem = task_info[task_name]['mem_gb']
        ax.plot(range(start, start + len(mem)), mem, label=task_name)
        start += len(mem)
    ax.legend()
    return plt
