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The primary structure of the AS/400's work management system is its storage pools or rather called as system pools. Sleek and elegant, they provide the memory management underpinnings for the AS/400's multitasking environment. The main task of these pools is to segment OS/400's working memory so that each subsystem can access its own specified piece of memory. By doing this, resource contention among different subsystems can be reduced. These pools allow administrators to provide dedicated resources to groups of jobs and to keep the resources separate. These pools allow administrators to control the job flow on the AS/400 server in a better manner so that more work can be obtained at a shorter span.

Storage pool management consists of dividing memory into different storage pools and assigning storage pools to individual subsystems. The default storage pool for the QBATCH and QPGMR subsystems is the “BASE” storage pool. Additional storage pools can be created based on the jobs executed in the batch. Memory is always allocated to other storage pools from the “BASE” storage pool. Whenever, a large job is processed in a pool and the job is lacking in memory resources, then memory may be allocated from different storage pools to the job automatically. Whenever jobs are being processed, records/programs required for processing the job from the pool may be either outdated or corrupted leading to database page faults and non-database page faults. These faults when left unattended, the job/batch processing may become slow leading to a poor system performance over a period of time. To avoid degradation of the system or rather the target AS/400 server, it is necessary to monitor the system pools continuously for the page faults. The AS400PoolTest test helps administrators in this regard!

This test auto-discovers the system pools of the target AS/400 server and for each system pool, this test reports the size of the pool and the maximum threads that can be active on the pool. In addition, this test reports the number of database pages and non-database pages available in each system pool. Using this test, administrators can also determine the number of database page faults and non-database page faults that were detected in each system pool. This way, administrators can determine the system pool on which maximum page faults are detected.

Measurement	Description	Measurement Unit	Interpretation
Pool_main_store_size	The amount of main storage, in kilobytes, in the system pool	KB	RAM and DASD are combined into a logical unit called main storage.
Reserved_pool_size	The amount of storage space in the pool reserved for system use.	KB
Max_active_threads	The maximum number of jobs or task threads that can be active in this pool at the same time.	Number	Generally, allowing a large number of jobs to get CPU time (called an activity level) is not desired. Performance may improve if the value of this measure is smaller. This implies that you should allow complete execution of a job before moving on to a new work.
DB_pages	Indicates the number of database pages that are available in this system pool.	Number	Database pages are the internal basic structure to organize the data in the disk or memory pool. These can be records of data in the disk or memory pool.
Non_DB_pages	Indicates the number of non-database pages that are available in this system pool.	Number	Generally, non-database pages are programs that are in the system pool.
DB_faults	Indicates the number of database page faults that were detected in this system pool.	Number	A page fault indicates that blocks of memory i.e., records or programs from disk are being read into main memory. Ideally, the value of these measures should be low. A high value for these measures may affect the system performance. To minimize the value of these measures, you can either increase the Pool main store size measure as well as decrease the Max active threads measure. Comparing the value of these measures across the system pools help administrators to determine the system pool on which maximum number of faults were detected and take remedial steps to boost the system performance.
Non_DB_faults	Indicates the number of non-database page faults that were detected in this system pool.	Number