Fire and forget
Tell the system to execute some code asynchronously and not care about when it finishes, nor the result.
Solution: Task abstraction in elixir. Tasks are processes meant to run a single action within their life-cycle
Practice:
Run a one-off action in Elixir to spawn the tasks under a supervision tree. We can easier to manage the processes(clean)
Task.Supervisor.start_child/2
The default strategy for the Task.Supervisor is :temporary - never restarted.
Implementation:
- In the
Applicationwe add aTask.Supervisor, is named such as: AwesomeTaskSupervisor - When we spawn a process, we start a child task with AwesomeTaskSupervisor name.
Task.Supervisor.start_child(AwesomeTaskSupervisor, process_func)
Fan-in/fan-out
Tell the system to execute consists of multiple operation. We run asynchronously, but care about the results. Example: uploading a bunch of docs to S3, sending a batch of emails to people.
Solution: Task without using a supervisor
Implementation:
- Using Enum.map/2 and Task.async/1 to generate the processes.
- Using Enum.map/2 and Task.await/1 to wait all of processes are done
Scheduling work
Tell the system run some work periodically every N minutes/hours/etc.
Solution: GenServer abstraction. We save the period rule in the genserver. Using Process.send_after/3 to trigger the handle_info/2 processing function.
Library: Quantum
Caching data
Tell the system cache the frequently data. Such as: caching the frequently response, temperature data.
Solution:
- Agents abstraction: a single process, therefore, we got bottleneck
- ETS: faster, support concurrency reads and writes
- GenServers
Library: https://github.com/sasa1977/con_cache
