Sidekiq Batches stuck in pending state

[Blokh]

Ruby version:
2.5.5
Rails version:
5.1.6
Sidekiq / Pro / Enterprise version(s):
sidekiq-pro (5.0.0)

Greetings,
For some reason, we've been encountering an issue of disappearing/stuck batch jobs.

Those jobs do not finish. does not enqueue and cannot be found in either Queue, Busy or Retryset.

they are stuck in a pending state in the batch until for some unknown reason they get "start" working again.
this time is random. sometimes at 3 am sometimes at 1 pm.

Does anyone else encounter this issue? was it resolved in the more recent sidekiq versions?

Thanks in advance,
Daniel

[Blokh]

One more question.
What are the possible reason for the batch, on success not to be called?

Currently, I've got a batch with all of his jobs finished successfully.
and the batch's on_success callback is not being received. even though the queue is empty.

What might be the cause of it?

[mperham]

If you have issues, it's always a good idea to update Sidekiq Pro. There have been numerous releases since 5.0.0. bundle up sidekiq-pro

Stuck batches are probably the #1 issue in Sidekiq.

• The cause is always the same: deployment kills the process, which leads to lost jobs.
• The workaround: enable super_fetch and restart the process to rescue any orphaned jobs.
• The solution: rework your deployment process so Sidekiq can shut down cleanly and not lose jobs in the first place.

https://github.com/mperham/sidekiq/wiki/Deployment#overview