Understand Performance Data for IBM i Servers

In order to understand and meaningfully analyse performance data on IBM i servers, you should preferably have a thorough understanding of all the factors affecting application performance on IBM i servers.  This is a very large topic and we do not attempt to cover it here.

In this section you will find brief descriptions of the IBM i performance data items provided by LANSA Composer's performance data collection, along with information on how the data is collected by LANSA Composer.  Please refer to the followings topics:

Performance Data Items for IBM i Servers

Performance Data Collection on IBM i Servers

 

Performance Data Items for IBM i Servers

In addition to the Common Performance Data Items, the following performance data items are provided when LANSA Composer is running on an IBM i server:

Item Description CPU Processing unit time used (in milliseconds) during the execution of this item. CPU DB Processing unit time used for database (in milliseconds) during the execution of this item. LckW Lock wait time (in milliseconds) during the execution of this item. PagF Page fault count during the execution of this item. TStg Temporary storage used in kilobytes TStg Delta The nett change in the TStg value during the execution of this item. I/O Disk I/O count during the execution of this item. I/O Async Disk I/O count (asynchronous I/O) during the execution of this item. I/O Sync Disk I/O count (synchronous I/O) during the execution of this item.

 

Performance Data Collection on IBM i Servers

On an IBM i server, performance data is collected using the QUSRJOBI application program interface provided by the operating system.  LANSA Composer uses the JOBI0150 and JOBI1000 formats to retrieve the information.

You can refer to IBM's documentation of the QUSRJOBI application program interface for further insights on the performance data items provided.