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dizzyVikon Ask HN: Share your personal website

I've been on a bit of a hiatus as we've got a new human to look after, but I do blog here, and intend to blog there once I have the time available again.

dizzyVikon Redis is fast – I'll cache in Postgres

I don't think this is a fair assessment. Had my benchmarks shown, say, that postgres crumbled under heavy write load then the conclusion would be different. That's exactly why I decided to do this - to see what the difference was.

dizzyVikon Redis is fast – I'll cache in Postgres

I completely agree that this is not relevant for anyone running such workloads, the article is not aimed at them at all.

Within the constraints of my setup, postgres came out slower but still fast enough. I don't think I can quantify what fast enough is though. Is it 1000 req/s? Is it 200? It all depends on what you're doing with it. For many of my hobby projects which see tens of requests per second it definitely is fast enough.

You could argue that caching is indeed redundant in such cases, but some of those have quite a lot of data that takes a while to query.

dizzyVikon Redis is fast – I'll cache in Postgres

I still end up recommending using postgres though, don't I?

dizzyVikon Redis is fast – I'll cache in Postgres

1. No persistence for redis. 2. Redis would get OOM killed. 3. The default config coming with the image was used. 4. Yes, I gave it 2 cpus.

I wanted to compare how would my http server behave if I used postgres for caching and what the difference would be if I used redis instead.

This benchmark is only here to drive the point that sometimes you might not even need a dedicated kv store. Maybe using postgres for this is good enough for your use case.

The term production environment might mean many things. Perhaps you're processing hundreds of thousands of requests per second then you'll definitely need a different architecture with HA, scaling, dedicated shared caches etc. However, not many applications reach such a point and often end up using more than necessary to serve their consumers.

So I guess I'm just trying to say keep it simple.

dizzyVikon Redis is fast – I'll cache in Postgres

There's a reason this is on my blog and not a paper in a journal. This isn't supposed to show the absolute speed of either tool, the benchmark is not set up for that. I do state that redis has more performance on the table in the blog post.

dizzyVikon Redis is fast – I'll cache in Postgres

Not on my computer right now but I think it's 45 bytes per value

dizzyVikon Redis is fast – I'll cache in Postgres

Author here. Redis is definitely faster. I was specifically not going for absolute peak performance for either redis or postgres - that would require going down to the wire protocols. The idea was emphasize that there' a "good enough" level of performance. Once you need that sort of speed - sure, there are ways to achieve it.

I've done a quick experiment with text embeddings on my blog, for recommended posts.

dizzyVikon Enums in Go

These both look like great tools. I'll give them a spin!