redis多大的key算大key？

一个key或是value大小最大是512M，这已经算大了的。redis单个实例最多能存多少个key键，每个值能存储多少个元素？

解决方法：

What is the maximum number of keys a single Redis instance can hold? and what is the max number of elements in a Hash, List, Set, Sorted Set?

Redis can handle up to 2^32 keys, and was tested in practice to handle at least 250 million keys per instance.

Every hash, list, set, and sorted set, can hold 2^32 elements.

In other words your limit is likely the available memory in your system.

从官网中找到了答案，可见一个单实例的redis最多能支持2^32个键，差不多就是2.5亿个，每个key中的值也是可以存 2^32行数据，所以服务器的内存才是我们所担心的。