Queue

The queue is the waiting line for action lists to be executed by the MUSH. Each time you enter an action list, it goes into the queue and stays there until its turn comes up, at which time the MUSH processes the commands and you see the results. The MUSH can execute thousands of commands every second, so normally you see results right away.

There are actually two distinct queues:

Incoming socket commands. These are run immediately, so a “look” or “@ps” will happen before any other softcode that is waiting to run. A socket may ‘burst’ up to 100 commands, then 1 per second after that.
Command queue. These enter the queue via @trigger, @force, or many other ways.

There is also a Wait queue, where commands queued via the @wait command go, and a Semaphore queue, where semaphore @waits go. These commands are moved to the command queue at the appropriate time, either when the @wait time elapses, or when the semaphore is @notified.

You can see which commands are currently queued with the @ps command, and with the getpids(), lpids() and pidinfo() functions. Queued commands can be cancelled with @halt and/or @drain.

Queue configuration

The player_queue_limit and owner_queues options affect queue admission.

The option ‘player_queue_limit’ controls how many action lists can be queued by one object at any given time. Wizards and objects with the Queue @power can queue more commands (equal to the player_queue_limit plus the current number of objects in the database, including garbage). An object that tries to queue past its limit is halted: its pending commands are wiped, it is set HALT, and its owner is told “Runaway object: <name>(<dbref>). Commands halted.” A player’s own typed commands are never counted against the limit, so a player whose objects have exhausted it can still act.

Normally each object has its own queue count, but if the ‘owner_queues’ option is enabled, objects share a queue count with their owner.

queue_chunk, queue_cost, and queue_loss are accepted compatibility settings, but the SharpMUSH scheduler does not read them. PennMUSH uses them for command batches and refundable or occasional lost penny charges; SharpMUSH has no built-in penny balance and does not charge for queueing. See compatibility economy.

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