7.2. Amount of Data Processed by a Standard Analytical Query #
Certain analytical queries require a large amount of RAM to be executed effectively, particularly:
joining two large analytical tables
aggregations over a large number of unique keys
sorting large analytical tables
The amount of RAM required for a specific OLAP workload depends on the number and size of analytical queries in the Postgres Pro AXE instance. Monitor the amount of available RAM and allocate additional RAM if required.
For the initial deployment, allocate 4 CPU cores per one analyst and approximately 6 GB of RAM per 1 CPU core reserved for executing analytical queries.
Monitor the amount of temporary files created by pgpro_axe every 24 hours and avoid peak values. Temporary files are located in the directory specified by the duckdb.temporary_directory configuration parameter.
If pgpro_axe lacks RAM for executing an analytical query, the associated OLAP data is placed in temporary files, which significantly increases the execution time. To maximize the total Postgres Pro AXE cluster throughput and the number of analytical queries executed per unit of time, process most analytical queries in RAM.
However, temporary files can be used when processing resource-intensive analytical queries with long execution time (hours).