We all know that IBM i is a very scalable platform. It supports businesses from the very small to the very large. However, as the workload running on an IBM i partition increases and becomes large, knowing the limits of your system becomes increasingly important.
IBM has documented the IBM i Maximum Capacities for many releases. This documentation identifies the “most of” various “things” within the operating system. Review this documentation to understand what these limits are – and to determine if you are nearing any limits. If you are near any limits, you should put plans in place to mitigate the issue (or perhaps submit a requirement to IBM to increase the limit).
The screen capture below shows the navigation within the IBM i Knowledge Center where the maximum capacities are documented and you can see the categories of limits that are included.
While it’s good to know maximum capacities, you probably want to be a bit more proactive if you are potentially nearing any of the limits. IBM has done some work to make this easier for you.
System Health Services are a part of the IBM i Services. If you are not familiar with the IBM i Services, you may want to read this blog I wrote about them.
With system health services, the IBM i operating system tracks a subset of the various system limits and has been increasing the number of limits that are tracked.
You can review the system limits by using SQL. You can also build triggers to enable automation so you do not have to manually review the limits that are tracked. In a future article, I’ll provide examples.
The database Health Center has support for system limits as well. You find it under Database → All Tasks → Health and Performance → Health Center.
When you launch the Health Center, you will find various tabs to review and analzye limits for your database.
The System Health Services page on IBM developer is a good place to start to learn more. It reviews the overall support and describes the limits that are tracked. It also contains a documentation PDF with a lot of useful information.
This blog post was edited for currency on April 13, 2020.
This blog post was originally published on IBMSystemsMag.com and is reproduced here by permission of IBM Systems Media.