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A cache is such a red flag when I'm doing a system design interview.

I ask people to design a system but the system itself is very write heavy. Like 50 writes per read imbalanced. People will often suggest a cache because it's in the standard interview prep but not actually think about why they need it. They just go right to "I need a cache somewhere".




> I ask people to design a system but the system itself is very write heavy. Like 50 writes per read imbalanced. People will often suggest a cache because it's in the standard interview prep but not actually think about why they need it.

I mean, it's a cool thought process to go "Ooh, maybe I can store up repeated things so I don't need to repeat an expensive access process often!" It's a byproduct of modern computing hardware that we frequently have the luxury of not thinking about caching very often.

I don't think you should punish people for considering a cache. Write caching is a thing, it might just not be applicable for the system you're considering.


Well yeah, if you can say all this in the interview then you will be fine. 90% of candidates will instead read "add cache to improve performance" in their interview prep guide and repeat it verbatim.


Ok if not cache then it must be hashtable?


To crack any IT interview, just breadth-first search the hashtable in a dictionary and you're golden.


lol, i don't get it.




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