How to check maximum parallel query count for processing of vertica?
In general, when running more than one query concurrently, both queries are sharing the system resources.
Queries on segmented tables run on all the nodes, and adding more nodes usually improve the run time of a query.
If a query does not get enough of a particular resource to run, then the system becomes a bottleneck and you may reach a limit.
In order to increase concurrency in such cases, the system must be expanded by adding more of that resource.
One can monitor the utilization via Vertica management console or via CLI manually,
For example, monitor correlation between concurrent queries count, CPU utilization, and queries elapsed time here:https://www.vertica.com/blog/vsql-visual-storytelling-through-query-language/