For customers thinking about using the PDELAY feature on ZRTDM in the near future, here is a list of recent PDELAY related APARs. These APARs will be shipped later this year with PUT 12 and are now available for download from the z/TPF website. It is highly recommended that customers download and integrate these APARs into their z/TPF environment if they intend to use PDELAY support.
What is PDELAY?
PDELAY is a file threshold for a delay-file pending short term pool residing in VFA. The value is set per record ID using the ZRTDM MODIFY command. At the time the BCA is flushed, if the BCA is older than the PDELAY threshold value, the buffer is purged rather than filed to DASD. It is a means to cut down on unnecessary I/O for transactions that have completed.
APAR PJ42789
This APAR solves a CTL-572 situation when a BCA is to be purged due to the BCA being older than the PDELAY threshold. The PDELAY path in the VFA reserve list refill routine attempts to flush the BCA and calls the BCA invalidate routine. The BCA invalidate routine assumes the BCA control area lock is not held upon entry, but in this case the lock was held at entry to reserve list refill processing.
The PDELAY logic in the CP was also made consistent with the delay file processing during system cycle.
More information on APAR PJ42789 can be seen at the following link:
http://www-01.ibm.com/support/docview.wss?crawler=1&uid=swg1PJ42789
APAR PJ43069
This APAR solves a situation where reserve list chain corruption could occur as well as orphaning a Fast and Main RSHT entry lock. The system may issue a CTL-571 catastrophic or CTL-572 dump for these held RSHT locks. If the CTL-571 catastrophic is not issued, the I-stream on which this processing occurred will end up in an infinite loop going to CVF3AL46 to re-add the same BCA to the reserve chain.
A performance improvement was also found in the VFA reserve list refill routine’s PDELAY path. File address decode was being invoked for a BCA to determine if it was a short term pool record. The call to decode was removed as the BCA must have gone through decode already; the flags to interrogate are already in the BCA.
Note: This APAR is marked as HIPER, but you are only at risk if you have PDELAY usage active for a set of record IDs with the ZRTDM MODIFY command.
More information on APAR PJ43069 can be seen at the following link:
http://www-01.ibm.com/support/docview.wss?crawler=1&uid=swg1PJ43069