gevent 为什么测试下来比多进程要慢很多？

为什么 gevent 比多进程慢那么多？是不是只有 gevent 作为 http 服务器的时候才有优势？对于这种主动请求的没优势？

gevent:40 秒
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start_time = time.time()
urls = ('http://www.baidu.com' for i in range(10000))
jobs = [gevent.spawn(requests.get, url) for url in urls]
#print(jobs)
gevent.joinall(jobs)
#print([job.value.status_code for job in jobs])
end_time = time.time()
print(end_time - start_time)
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multiprocessing：12 秒
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def req(url):
    return requests.get(url).status_code

if __name__ == '__main__':
    start_time = time.time()
    p = Pool(32)
    res_l = []
    for i in range(10000):
        res = p.apply_async(req, args=('http://www.baidu.com',))
        res_l.append(res)
    p.close()
    p.join()
    #print(len([i.get() for i in res_l]))
    end_time = time.time()
    print(end_time - start_time)
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