[mperham]

Sidekiq has a lot of code to deal with both of these issues.

Sidekiq does not guarantee ordering within a queue; that’s a terrible, very expensive guarantee. Developers don’t want total ordering of jobs within a queue, they want to know that Job A will fully execute before Job B. There might be 1000 other jobs in the queue that are completely independent of that ordering but we’ve screwed ourselves by forcing total queue ordering. Instead Sidekiq Pro provides a workflow API, Sidekiq::Batch, which allows the developer to author higher-level workflows for Job A -> Job B which provides the ordering guarantee.

For poison pills, we detect jobs which were running when a Sidekiq process died. If this happens multiple times, the job will be sent to the dead letter queue so the developer can deal with them manually. If they were part of a Batch, the workflow will stall until the developer fixes the issue and executes the job manually to resume the workflow.