10-caching.adoc

Caching

Dshackle can be configured to cache blockchain data. It can be a hot in-memory cache, and optional cold Redis-based cache.

Dshackle has enough information to effectively cache data and evict outdated values. If some data has been removed from the blockchain, for example when block was replaced with another block at the same height, then the old values are immediately evicted from the caches.

In-memory cache

Dshackle keeps latest blocks in memory (by default 64 blocks)

Redis cache

Dshackle can optionally cache blocks and transactions in Redis cache. The values are cached up to 1 hour, but fresh blocks and transactions are cached for shorter period.

It makes sense to reuse the same Redis cache between multiple instances of the Dshackle.

Basic config (dshackle.yaml)

cache:
  redis:
    enabled: true

Full config (dshackle.yaml)

cache:
  redis:
    enabled: true
    host: 127.0.0.1
    port: 6379
    db: 0
    password: passw0rd!

Table 1. Options

Name	Default Value	Description
enabled	false	Set to true if Dshackle should use Redis for caching
host	127.0.0.1	Redis host
port	6379	Redis port
db	0	Redis database
password	—	Password if Redis requires authentication. The value can be read from Environment variable, to do that specify it as ${REDIS_PASSWORD}, where REDIS_PASSWORD is the name of the variable