cache key length limit

[dongmei761]

I'm wondering if the cache key has a length limit? Is it the same with the length limit of String on V8? Will these long keys impact the performance?

[danielway]

Hi there @dongmei761.

It seems that your guess is correct; key length will be limited by string sizes for the environment. The standard answer is 2^27 characters. [1]

Regarding performance impacts, once again there are differences environment-to-environment. It seems most browsers will place keys into a hash-table making their lookup efficient and not dependent on key length. [2]

References:
[1] https://stackoverflow.com/a/28841863
[2] https://stackoverflow.com/a/13940271