Re:A Collection Of Redis Use Cases
by simonw on Tuesday February 16, 2010 @12:44PM
(#1129275)
These are really useful. I've been telling anyone who will listen that Redis is a very different beast from the other NOSQL / Document stores out there - it scales down to small applications beautifully and makes a whole class of large-scale write problems (like real-time statistics) approachable for smaller projects.
[ Parent
| on HN ]
it scales down to small applications beautifully
This is worth highlighting. In Rails, for example, the integration for Redis is seven lines of code (they're in my last blog post), and then the Rails cache you know and love is suddenly magic. It requires no significant amount of developer resources to integrate, minimal sysadmin skills to get running, and coexists beautiful with whatever you use for data persistence right now. In all of these respects it is a lot like memcached. (Or like memcachedb except without the periodic disk flush that gives your users 5 second response times.)
But wouldn't it require lots of RAM? My web server only has 512MB (or 256, not sure), therefore I have not seriously considered it yet. I'd love to use it, but it would cost me a lot to move to a better server.
Also, none of the root servers you can rent seem to have decent amounts of memory.
The new virtual memory feature of Redis 2.0 allows you to swap data to disk and keep a minimal subset (the keyset, only values are swapped, never keys) in ram (1M keys would require 160mb of memory). You could keep only the most frequently used values in ram (and the keyset) to minimize memory usage.