redis - More than a cache

1. redis More than a cache
2. "Software engineering enthusiast. Moved to the dark side. Now executive and strong advocate on lean management. Speaker, author, lateral thinker & happy." – @devpg
3. redis == Remote Dictionary Server - Key-value store - Single-threaded - In-memory but persistent on disk - Implemented in C - Human readable protocol - Well documented - Open source - Sponsored by VMware
4. Data types - Strings (binary-safe) - Hashes - Lists - Sets - Sorted Sets Hello World // String user:23 name @devpg // Hash "b", "b", "a", "c" // List "b", "a", "c" // Set "a", "b", "c" // Sorted Set
5. Commands - Atomic + specific >> SADD following "@devpg" "@TwitterEng" // Multiple member arguments since 2.4 (integer) 1 >> SISMEMBER following "@TwitterEng" (integer) 1 >> SISMEMBER following "@Twitter" (integer) 0 >> SADD followers "@devpg" "@TechBerlin" (integer) 1 >> SINTERSTORE overlap following followers (integer) 1 >> SMEMBERS overlap 1) "@devpg"
6. Commands Redis Any data store 1. Read 2. Filter / modify 3. Update 1. Filter / modify
7. Commands More: redis.io/commands
8. Performance (on my heavily used MacBook Air Core2Duo) ./redis-benchmark ====== PING (inline) ====== 22624.43 requests per second ====== MSET (10 keys) ====== 13642.57 requests per second ====== SET ====== 20161.29 requests per second ====== GET ====== 21834.06 requests per second ====== INCR ====== 20449.90 requests per second ====== LPUSH ====== 21097.05 requests per second ====== LPOP ====== 21598.27 requests per second ====== SADD ====== 21276.60 requests per second ====== SPOP ====== 22421.52 requests per second ====== LRANGE (first 100) == 16920.47 requests per second ====== LRANGE (first 300) == 11737.09 requests per second ====== LRANGE (first 450) == 9803.92 requests per second [...]
9. Pipelining Redis Redis
10. Transactions aka. Multi/Exec/Discard Redis 1. Multi 2. Queuing commands 3. Exec / discard Redis
11. Transactions aka. Multi/Exec/Discard - Atomic execution >> MULTI QUEUED >> SADD following "@devpg" "@TwitterEng" QUEUED >> SADD followers "@devpg" "@TechBerlin" QUEUED >> SINTER following followers QUEUED >> EXEC 1) (integer) 1 2) (integer) 1 3) 1) "@devpg"
12. Transactions aka. Multi/Exec/Discard >> GET item_42 // stock=1 [... check > 0 ...] >> MULTI QUEUED >> DECR item_42 QUEUED >> EXEC 1) (integer) 0 >> GET item_42 // stock=1 [... check > 0 ...] >> MULTI QUEUED >> DECR item_42 QUEUED >> EXEC 1) (integer) -1 << Client A >> << Client B >>
13. Transactions aka. Multi/Exec/Discard Redis
14. Transactions aka. Multi/Exec/Discard + Watch/Unwatch >> WATCH item_42 OK >> GET item_42 // stock=1 [... check > 0 ...] >> MULTI QUEUED >> DECR item_42 QUEUED >> EXEC 1) (integer) 0 >> WATCH item_42 OK >> GET item_42 // stock=1 [... check > 0 ...] >> MULTI QUEUED >> DECR item_42 QUEUED >> EXEC (nil) << Client A >> << Client B >>
15. Persistence - Asynchronously → Won't slow down operations - Delay configurable - Different modes: - RDB - AOF - Disabled save <every X sec> <if at least X keys changed> appendonly yes
16. Replication slaveof <Host> <Port> - Master-slave(s) approach - Non-blocking on master-side - Use cases: - Scalability → slaves for read-only queries - Redundancy
17. Limitations - Data must fit in memory → Cluster-support (at least not before version 3.0) - No user/ roles/ privileges - even authentication optional - No data encryption support
18. Pub/Sub >> SUBSCRIBE java 1) "subscribe" 2) "java" 3) (integer) 1 1) "message" 2) "java" 3) "hello world" >> PUBLISH java "hello world" (integer) 1 >> PUBLISH Java "hello world" (integer) 0 << Client A >> << Client B >>
19. Bindings for ... - ActionScript - C - C# - C++ - Clojure - Common Lisp - Dart - Erlang - Fancy - Go* - Haskell - Io - Java - Lua - Node.js - Objective-C - Perl - PHP - Pure Data - Python - Ruby - Scala - Smalltalk - Tcl * Just as much clients for Go (5) as for Java (5)!! WTF!?! :-)
20. Spring Data - redis - Requires > redis 2.0 (2.2 recommended) - Support for multiple clients (Jedis, JRedis, SRP, RJC) - RedisTemplate, collections, atomic counter - Exception translation - Pubsub support - Implementation for Spring 3.1 cache abstraction