Method _update_prefetch_count

celery/worker/consumer/consumer.py:269–286

Update prefetch count after pool/shrink grow operations. Index must be the change in number of processes as a positive (increasing) or negative (decreasing) number. Note: Currently pool grow operations will end up with an offset of +1 if the initial

(self, index=0)

        )

    def _update_prefetch_count(self, index=0):
        """Update prefetch count after pool/shrink grow operations.

        Index must be the change in number of processes as a positive
        (increasing) or negative (decreasing) number.

        Note:
            Currently pool grow operations will end up with an offset
            of +1 if the initial size of the pool was 0 (e.g.
            :option:`--autoscale=1,0 <celery worker --autoscale>`).
        """
        num_processes = self.pool.num_processes
        if not self.initial_prefetch_count or not num_processes:
            return  # prefetch disabled
        self.initial_prefetch_count = (
            self.pool.num_processes * self.prefetch_multiplier
        )
        return self._update_qos_eventually(index)

    def _update_qos_eventually(self, index):
        return (self.qos.decrement_eventually if index < 0