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- What does Redis do when it runs out of memory? 7 answers
What happens to a Redis data store if the data exceeds available ram?
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What happens to a Redis data store if the data exceeds available ram?
I think there is a store size setting in redis config that will stop you adding more data than can fit in the store you have set up. If you set up a store that doesn't fit in physical memory, it will simply ask the OS for more memory and some of it will be paged to disk, with obvious performance consequences.
The next version of redis has its own virtual memory implementation which can store less frequently used keys on disk - http://antirez.com/post/redis-virtual-memory-story.html