Hammer application, responsible for starting the backend worker pools.

Configured with the :hammer environment key:

• :backend, Either a tuple of {module, config}, or a keyword-list of separate, named backends. Examples: {Hammer.Backend.ETS, []}, [ets: {Hammer.Backend.ETS, []}, ...]
• :suppress_logs, if set to true, stops all log messages from Hammer

General Backend Options

Different backends take different options, but all will accept the following options, and with the same effect:

• :expiry_ms (int): expiry time in milliseconds, after which a bucket will be deleted. The exact mechanism for cleanup will vary by backend. This configuration option is mandatory
• :pool_size (int): size of the backend worker pool (default=2)
• :pool_max_overflow int(): number of extra workers the pool is permitted to spawn when under pressure. The worker pool (managed by the poolboy library) will automatically create and destroy workers up to the max-overflow limit (default=0)

Example of a single backend:

config :hammer,
  backend: {Hammer.Backend.ETS, [expiry_ms: 60_000 * 60 * 2]}

Example of config for multiple-backends:

config :hammer,
  backend: [
    ets: {
      Hammer.Backend.ETS,
      [
        ets_table_name: :hammer_backend_ets_buckets,
        expiry_ms: 60_000 * 60 * 2,
        cleanup_interval_ms: 60_000 * 2,
      ]
    },
    redis: {
      Hammer.Backend.Redis,
      [
        expiry_ms: 60_000 * 60 * 2,
        redix_config: [host: "localhost", port: 6379],
        pool_size: 4,
      ]
    }
  ]