z/TPFDF data collection infrastructure updates provide changes to the way that z/TPFDF data collection statistics are collected.
These updates include the following changes:
- Statistics are collected on a per-SW00SR basis. All data collection statistics are collected for the length of time that the subfile is open.
- A DFUEX user exit is available during close processing. Applications or utilities can use this user exit to query the individual subfile statistics, such as the number of I/Os that were performed for a particular subfile, and take appropriate actions. One use for this is to allow real-time monitoring of z/TPFDF subfile sizes to detect anomalies as early as possible.
- Individual subfile statistics are collected continuously. These statistics are added to a z/TPFDF central collection area in memory whenever a subfile is closed. The central collection area can potentially be accessed by other utilities.
- If you enter the ZUDFC START command to turn on z/TPFDF data collection, the newly collected statistics are used to update the z/TPFDF collection area. Because the counters in the common collection area are updated only when a z/TPFDF subfile is closed, counter contention might occur less frequently.
For more information, see the APEDITs for APAR PI22609 and APAR PJ42451.