FRESH

Hacker News

Redis 8.8: New array data structure, rate limiter, performance improvements

153 points by ksec

by simonw

1 subcomments

> Rate limiting is one of the most common Redis use cases. Traditionally, users implemented rate limiters using server-side Lua scripts combined with client logic. In Redis 8.8, we introduce a window counter rate limiter (by @raffertyyu, together with the Redis team).
I had a look for this and it turns out it's slightly mis-described there - it's not a window counter, it's a "GCRA (Generic Cell Rate Algorithm)" - a leaky bucket algorithm. Code here: https://github.com/redis/redis/blob/unstable/src/gcra.c
The code comments say it was heavily influenced by https://github.com/brandur/redis-cell by Brandur Leach.
It's a neat algorithm (I just learned about it today) - it only needs to store a single integer for each rate-limited key, which is the "Theoretical Arrival Time" when the bucket would next be empty.

by 9dev

5 subcomments

While I love Redis as a versatile tool for external data structures, it's still lacking in two areas IMHO:
One, it would be cool to be able to embed it, similar to sqlite, directly into applications.
Two, the HA story is so much more complicated than it should be. I totally acknowledge that concurrency and distributed computing is hard, but it should not require reading heaps of documentation and understanding two entirely separate multi-node approaches only to figure out there are lots of subtle strings attached that make it impractical for many applications.

by tapoxi

10 subcomments

Where did everyone end up on the Redis/Valkey split? Is there still a reason to use Redis after the license kerfuffle?

by epolanski

1 subcomments

There's also a separate blog post that goes into the details of why existing data structures Redis already supported, which could provide array-like behavior, weren't good enough:
https://redis.io/blog/diving-deep-into-rediss-new-array-data...

by focusgroup0

2 subcomments

given his ds4 project, likely collaborated with DeepSeek for this release:
https://github.com/antirez/ds4

by caraphon

0 subcomment

window counter rate limiter!
This is awesome!
And arrays look great too. Lots to play with.

0 subcomment

by Xotic007

0 subcomment

by fga_qwrh

0 subcomment

And here we see the reason for the sudden AI enthusiasm of Redis authors: array data structures are used in AI. This was clear weeks ago.
The website looks like openclaw's website.