> The main issue is that a reader might mistake Redis as a 2X faster postgres. Memory is 1000X faster than disk (SSD) and with network overhead Redis can still be 100X as fast as postgres for caching workloads.

Your comments suggest that you are definitely missing some key insights onto the topic.

If you, like the whole world, consume Redis through a network connection, it should be obvious to you that network is in fact the bottleneck.

Furthermore, using a RDBMS like Postgres may indeed imply storing data in a slower memory. However, you are ignoring the obvious fact that a service such as Postgres also has its own memory cache, and some query results can and are indeed fetched from RAM. Thus it's not like each and every single query forces a disk read.

And at the end of the day, what exactly is the performance tradeoff? And does it pay off to spend more on an in-memory cache like Redis to buy you the performance Delta?

That's why real world benchmarks like this one are important. They help people think through the problem and reassess their irrational beliefs. You may nitpick about setup and configuration and test patterns and choice of libraries. What you cannot refute are the real world numbers. You may argue they could be better if this and that, but the real world numbers are still there.

> If you, like the whole world, consume Redis through a network connection, it should be obvious to you that network is in fact the bottleneck.

Not to be annoying - but... what?

I specifically _do not_ use Redis over a network. It's wildly fast. High volume data ingest use case - lots and lots of parallel queue workers. The database is over the network, Redis is local (socket). Yes, this means that each server running these workers has its own cache - that's fine, I'm using the cache for absolutely insane speed and I'm not caching huge objects of data. I don't persist it to disk, I don't care (well, it's not a big deal) if I lose the data - it'll rehydrate in such a case.

Try it some time, it's fun.

> And at the end of the day, what exactly is the performance tradeoff? And does it pay off to spend more on an in-memory cache like Redis to buy you the performance Delta?

Yes, yes it is.

> That's why real world benchmarks like this one are important.

That's not what this is though. Just about nobody who has a clue is using default configurations for things like PG or Redis.

> They help people think through the problem and reassess their irrational beliefs.

Ok but... um... you just stated that "the whole world" consumes redis through a network connection. (Which, IMO, is wrong tool for the job - sure it will work, but that's not where/how Redis shines)

> What you cannot refute are the real world numbers.

Where? This article is not that.

> If you, like the whole world, consume Redis through a network connection

I think "you are definitely missing some key insights onto the topic". The whole world is a lot bigger than your anecdotes.