skills/redis-development/rules/conn-pooling.md

title	impact	impactDescription	tags	description	alwaysApply
Use Connection Pooling or Multiplexing	HIGH	Reduces connection overhead by 10x or more	connections, pooling, multiplexing, performance	Use Connection Pooling or Multiplexing	true

Use Connection Pooling or Multiplexing

Reuse connections via a pool or multiplexing instead of creating new connections per request.

Correct: Use a connection pool.

Python (redis-py):

import redis

# Good: Connection pool - reuses existing connections
pool = redis.ConnectionPool(host='localhost', port=6379, max_connections=50)
r = redis.Redis(connection_pool=pool)

Java (Jedis):

import redis.clients.jedis.JedisPooled;

// JedisPooled manages a connection pool internally
try (JedisPooled jedis = new JedisPooled("redis://localhost:6379")) {
    jedis.set("testKey", "testValue");
}

Correct: Use multiplexing (Lettuce, NRedisStack).

// Lettuce uses multiplexing by default - single connection handles all traffic
RedisClient client = RedisClient.create("redis://localhost:6379");
StatefulRedisConnection<String, String> connection = client.connect();

// All commands share the single connection efficiently
connection.sync().set("key", "value");

Incorrect: Creating new connections per request.

Python (redis-py):

# Bad: New connection every time
def get_user(user_id):
    r = redis.Redis(host='localhost', port=6379)  # Don't do this
    return r.get(f"user:{user_id}")

Java (Jedis):

// Bad: Creating new client per request
public String getUser(String userId) {
    try (UnifiedJedis jedis = new UnifiedJedis("redis://localhost:6379")) {
        return jedis.get("user:" + userId);  // Don't do this
    }
}

Pooling vs Multiplexing:

• Pooling: Multiple connections shared across requests (redis-py, Jedis, go-redis)
• Multiplexing: Single connection handles all traffic (NRedisStack, Lettuce)
• Multiplexing cannot support blocking commands (BLPOP, etc.) as they would stall all callers

Reference: Connection Pools and Multiplexing