gtpm1m41TPF V4R1 Migration Guide: 3.1 to 4.1

Path Information Unit (PIU) Trace Facility

The path information unit (PIU) trace facility provides a detailed trace of the data, or PIUs, transferred between a TPF 4.1 system and channel-to-channel (CTC), adjacent link station (ALS), and Network Control Program (NCP) resources. Each time the TPF 4.1 system sends or receives a PIU, the transmission header (TH), request/response header (RH), and some or all of the request/response unit (RU) associated with that PIU are stored in the PIU trace table when the PIU trace facility is active.

Note:
Advanced Communications Function/Trace Analysis Program (ACF/TAP) is no longer supported in the TPF 4.1 system.

The following enhancements were made to the PIU trace facility for the TPF 4.1 system: