A couple of weeks/months ago, when I would submit a batch, requests would start getting marked a “completed” virtually instantly, and the whole batch would finish in a few minutes. More recently, I’ve submitted identical batches which hang at “0 completed tasks” for 24 hours until they expire.
That could be chalked up to the servers being busy. However, I have also had situations where I was waiting hours for a batch, and then resubmitted the batch again, and the resubmitted batch ran instantly while the original batch continued to hang until it expired hours later. Whatever scheduling system is being used, it seems odd that two identical batches from the same user could be scheduled so differently. This also makes it quite hard to use the batch API as I can’t tell whether I’m waiting for my tasks to be scheduled, or if my batch has somehow been “forgotten” and will just expire in 24 hours.
I should also mention that status.openai.com has not shown any issues over the periods where I’ve seen this behavior.