XCOMM0895E ZIIP PROCESSING TERMINATED DUE TO ABEND - REASON CODE=00000002 with ZIIP=NO

Products

• XCOM Data Transport - z/OS

Issue/Introduction

After applying maintenance to XCOM Data Transport for z/OS 12.0.3, users may encounter the following issues:

• File transfers fail with error XCOMM0895E ZIIP PROCESSING TERMINATED DUE TO ABEND - REASON CODE=00000002.
• The system log may show related abends such as CCSR010E XCOMSTSK U3999.
• These failures typically occur when the configuration is explicitly set to ZIIP=NO.
• Changing the configuration to ZIIP=YES resolves the failure and allows transfers to proceed successfully.

Environment

• Product: XCOM Data Transport for z/OS
• Release: 12.0 Service Pack 03
• Component: zIIP Exploitation / Broadcom Common Services zIIP Enablement Service

Cause

A defect in XCOM 12.0.3 causes the zIIP enablement "black box" (provided by Broadcom Common Services) to be incorrectly called even when ZIIP=NO is configured. This leads to an abend because the required task control blocks (TCBs) for zIIP processing are not initialized when the feature is disabled.

 

Resolution

Recommended Configuration

Broadcom recommends maintaining the default setting of ZIIP=YES in the XCOM Default configuration.

• Operational Impact: There are no operational issues with this setting.
• Benefits: It offloads CPU-intensive functions (such as data compression and decompression) to zIIP specialty processors, reducing the load on general processors and lowering overall computing costs.

Fix for ZIIP=NO Failures

If your site requires running with ZIIP=NO, apply the following maintenance to resolve the abends:

• PTF LU19196: CCSR010E XCOMSTSK U3999 OR S46D ABENDS AFTER TRANSFER

This PTF corrects the improper call to the zIIP black box when processing is disabled.

Additional Information

• To monitor zIIP usage, use the modify command: F xcom_stc,ZIIP,STATUS.
• For maximum efficiency when using zIIP, ensure that PACK=LENGTH is specified for transfers to ensure data blocks meet the 4K minimum size requirement for offloading.

XCOM issues this message when the ZIIP interface component of Common Services has abended with U3999. The number in the message is the reason code associated with the abend.

In the ZIIPficitation black box, reason code xxxx0002 is documented to mean 'TASKCB@ IS 0'. 

The TASKCB@ is the anchor of a control block that holds information about the ZIIP black box. This anchor is set when the ZIIP interface is initialized. Therefore reason code 0002 means that ZIIP services are being improperly called for a TCB for which ZIIP has not been initialized, which is what LU19196 corrects.

Therefore, apart from what is documented in the description of LU19196, this confirms that the resolution provided is correct