As discussed today with Tal Doron in vienna we have the following feature request for the XAP product.
Length of a FIFO group via metrics or statistics API.
We need to publish this metric to some monitoring system to create real time dashboards showing the queue (FIFO group) length and build alarms etc based on this.
We tried 3 ways to do this:
have a dedicated thread which samples the FIFO group via performing a count query with the given FIFO grouping criteria
incrementing and decrementing a counter object in the space via change API within transaction
incrementing and decrementing a counter within a space filter
We think it is also useful for other customers to get easy and efficient access to this information because queue length is always an important metric to understand system behaviour/saturation and find bottlenecks.
This metric should be accessible within a GSC/PUI. For us it is enough to get the length of the FIFO group based on a single space instance, we do not need to get the total length across the cluster which of course is "more difficult/expensive" to obtain.