IPIC considerations

When running the Gateway daemon under load and using IPIC connected servers, you might need to increase the size of the JVM heap for the Gateway daemon if performance problems are encountered.

When running with container sizes greater than 1 MB, it might be necessary to increase the JVM resources for the Gateway daemon and CICS®.

The -Xmx and -Xss parameters might need to be changed for the Gateway daemon.
The following values might need to increase for a CICS TS server.
  • MEMLIMIT - Is the limit for above-the-bar storage for the CICS server. Abend codes AITJ and APCG are an indication that MEMLIMIT might be too small.
  • EDSALIM - The EDSALIM system initialization parameter specifies the upper-limit of the total amount of storage within which CICS can allocate the individual extended dynamic storage areas (EDSAs) that reside above 16 MB but below 2 GB. Abend code AIPE is an indication that the EDSALIM memory might be too small.

For more information about abend codes and their meaning, see CICS Transaction Servers.

For information about how statistics might indicate that a JVM is short of heap storage see JVM stress causing poor performance in the Gateway daemon.

While the default maximum heap size (128MB) is adequate for an SNA or TCP/IP workload, it might be necessary to increase this to 256MB or 512MB for an IPIC workload.


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Timestamp icon Last updated: Tuesday, 19 November 2013


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