set_point_queue_depth

Arguments

Returns

t on success, otherwise an error message.

Description

The DataHub has a special queueing mechanism for point changes that get sent to Gamma. If the DataHub receives incoming point changes faster than Gamma can process them, it puts the new values into a queue for that point. When Gamma is ready to process the next value of that point, it receives the earliest value from that queue, then the next value, and so on, in time-sequential order.

This function allows you to set the depth of this queue, in other words, the number of values per point that the DataHub will store in the queue. The default depth is 3. We recommend setting the queue depth as small as possible, since a deep queue will decrease Gamma's response time. If you want to minimize the response time and always use the very latest value, you can set N to 0 or 1, which effectively eliminates the queueing behavior altogether.

See also get_point_queue_depth and get_point_queue_count.