A taskprocessor is a serialized work queue. You put a work item in, and then it gets handled. Internally they’re used all over the place. Overloaded means that the rate at which work items are being queued exceeds the rate at which they are being processed and handled. The channel:all receives all the messages relating to every channel in the system, and is used by things that want to know what is going on. Ring all will certainly produce a ton of work items. I always think of ring all as essentially a DoS attack. Old firmware wouldn’t cause an issue, purely depends on the underlying system characteristics and usage patterns. We’ve tweaked things here and there in Asterisk to try to help speed up processing of work items in certain scenarios, but there are still some that just hammer things.