9812407f76
This commit reimplements how we monitor Sidekiq processes that are forked from the Unicorn master process. Prior to this change, we rely on `Jobs::Heartbeat` to enqueue a `Jobs::RunHeartbeat` job every 3 minutes. The `Jobs::RunHeartbeat` job then sets a Redis key with a timestamp. In the Unicorn master process, we then fetch the timestamp that has been set by the job from Redis every 30 minutes. If the timestamp has not been updated for more than 30 minutes, we restart the Sidekiq process. The fundamental flaw with this approach is that it fails to consider deployments with multiple hosts and multiple Sidekiq processes. A sidekiq process on a host may be in a bad state but the heartbeat check will not restart the process because the `Jobs::RunHeartbeat` job is still being executed by the working Sidekiq processes on other hosts. In order to properly ensure that stuck Sidekiq processs are restarted, we now rely on the [Sidekiq::ProcessSet](https://github.com/sidekiq/sidekiq/wiki/API#processes) API that is supported by Sidekiq. The API provides us with "near real-time (updated every 5 sec) info about the current set of Sidekiq processes running". The API provides useful information like the hostname, pid and also when Sidekiq last did its own heartbeat check. With that information, we can easily determine if a Sidekiq process needs to be restarted from the Unicorn master process. |
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| .. | ||
| environments | ||
| initializers | ||
| locales | ||
| application.rb | ||
| boot.rb | ||
| cdn.yml.sample | ||
| database.yml | ||
| deploy.rb.sample | ||
| dev_defaults.yml | ||
| discourse.config.sample | ||
| discourse.pill.sample | ||
| discourse_defaults.conf | ||
| environment.rb | ||
| logrotate.conf | ||
| multisite.yml.production-sample | ||
| nginx.sample.conf | ||
| projections.json | ||
| puma.rb | ||
| routes.rb | ||
| sidekiq.yml | ||
| site_settings.yml | ||
| spring.rb | ||
| thin.yml.sample | ||
| unicorn.conf.rb | ||
| unicorn_launcher | ||
| unicorn_upstart.conf | ||