1[Note: this is the Redis manifesto, for general information about 2 installing and running Redis read the README file instead.] 3 4Redis Manifesto 5=============== 6 71 - A DSL for Abstract Data Types. Redis is a DSL (Domain Specific Language) 8 that manipulates abstract data types and implemented as a TCP daemon. 9 Commands manipulate a key space where keys are binary-safe strings and 10 values are different kinds of abstract data types. Every data type 11 represents an abstract version of a fundamental data structure. For instance 12 Redis Lists are an abstract representation of linked lists. In Redis, the 13 essence of a data type isn't just the kind of operations that the data types 14 support, but also the space and time complexity of the data type and the 15 operations performed upon it. 16 172 - Memory storage is #1. The Redis data set, composed of defined key-value 18 pairs, is primarily stored in the computer's memory. The amount of memory in 19 all kinds of computers, including entry-level servers, is increasing 20 significantly each year. Memory is fast, and allows Redis to have very 21 predictable performance. Datasets composed of 10k or 40 millions keys will 22 perform similarly. Complex data types like Redis Sorted Sets are easy to 23 implement and manipulate in memory with good performance, making Redis very 24 simple. Redis will continue to explore alternative options (where data can 25 be optionally stored on disk, say) but the main goal of the project remains 26 the development of an in-memory database. 27 283 - Fundamental data structures for a fundamental API. The Redis API is a direct 29 consequence of fundamental data structures. APIs can often be arbitrary but 30 not an API that resembles the nature of fundamental data structures. If we 31 ever meet intelligent life forms from another part of the universe, they'll 32 likely know, understand and recognize the same basic data structures we have 33 in our computer science books. Redis will avoid intermediate layers in API, 34 so that the complexity is obvious and more complex operations can be 35 performed as the sum of the basic operations. 36 374 - Code is like a poem; it's not just something we write to reach some 38 practical result. Sometimes people that are far from the Redis philosophy 39 suggest using other code written by other authors (frequently in other 40 languages) in order to implement something Redis currently lacks. But to us 41 this is like if Shakespeare decided to end Enrico IV using the Paradiso from 42 the Divina Commedia. Is using any external code a bad idea? Not at all. Like 43 in "One Thousand and One Nights" smaller self contained stories are embedded 44 in a bigger story, we'll be happy to use beautiful self contained libraries 45 when needed. At the same time, when writing the Redis story we're trying to 46 write smaller stories that will fit in to other code. 47 485 - We're against complexity. We believe designing systems is a fight against 49 complexity. We'll accept to fight the complexity when it's worthwhile but 50 we'll try hard to recognize when a small feature is not worth 1000s of lines 51 of code. Most of the time the best way to fight complexity is by not 52 creating it at all. 53 546 - Two levels of API. The Redis API has two levels: 1) a subset of the API fits 55 naturally into a distributed version of Redis and 2) a more complex API that 56 supports multi-key operations. Both are useful if used judiciously but 57 there's no way to make the more complex multi-keys API distributed in an 58 opaque way without violating our other principles. We don't want to provide 59 the illusion of something that will work magically when actually it can't in 60 all cases. Instead we'll provide commands to quickly migrate keys from one 61 instance to another to perform multi-key operations and expose the tradeoffs 62 to the user. 63 647 - We optimize for joy. We believe writing code is a lot of hard work, and the 65 only way it can be worth is by enjoying it. When there is no longer joy in 66 writing code, the best thing to do is stop. To prevent this, we'll avoid 67 taking paths that will make Redis less of a joy to develop. 68