Performance Best Practices for z/OS Connect

Threads, Java heap, MEMLIMIT, REGION (OpenAPI 2)

To ensure your z/OS Connect server is running at an optimal level, make sure to carefully configure the Java heap, MEMLIMIT, and Region values while continuously monitoring your server as the workload is running. This IBM documentation will provide an overview of environment variables that directly correlate to how to calculate your Java heap size, MEMLIMIT, as well as how to monitor these values to enable your server to perform at an optimal level.

Configuration parameters in IBM z/OS Connect (OpenAPI 2)

Changing your default Configuration parameters enables you to accommodate a variety of workloads and deployment on z/OS Connect. This link provides a detailed explanation of different connection types, security options, and other configuration settings you should know.

GCPs, zIIPs and cryptographic processors (z/OS Connect OpenAPI 2)

Work that is eligible for zIIP offload will first arrive at the GCPs (General Processor Complex) and then be forwarded to an available zIIP. A balance of GCPs and zIIPs is required to efficiently handle the specific mix of processor requests for an environment. Additionally, cryptographic processors can be used to offload crypto-specific requests from the GCPs. Usage details may be obtained from SMF 70 subtype 1 and SMF 72 subtype 3 records. 

Enabling hardware cryptography for Liberty for z/OS using Java 8 

This document provides the steps necessary to enable the IBMJCECCA and IBMJCEHYBRID providers to make use of hardware cryptography, and to provide failover from hardware to software providers when running in a Liberty for z/OS server.

Enabling hardware cryptography for Liberty for z/OS using Java 11 

This document provides the steps necessary to enable the Z Security, IBMJCECCA and IBMJCEHYBRID providers to make use of hardware cryptography, and to provide failover from hardware to software providers when running with Java 11 in a Liberty for z/OS server. 

WLM service classes, report classes, and CPU activity (z/OS Connect OpenAPI 2)

Learn how to use the SMF 72 records to observe the workload activity of a service class and the report class of both a z/OS Connect server & a specific API. Identify how the SMF 70 records are utilized to observe CPU activity on your LPAR as well.

Enabling Asynchronous TCP/IP sockets I/O for Liberty on z/OS

Performance and scalability may be obtained by enabling asynchronous TCP/IP sockets I/O for Liberty (AsyncIO). This is performed by defining the security setup to permit ZOSAIO once the Angel process is started.

Configuring connection pooling for database connections

Enable connection pooling in the IBM z/OS Connect server to improve the efficiency of resource access. The link includes example code that uses the connectionManager element in the server.xml file to define a connection pool for a data source.

Configuring connection pooling for database connections

This page provides the Name, Type, Default value, and Descriptions of the variables for connectionFactory, connectionManager, containerAuthData, jaasLoginContextEntry, & recoveryAuthData configuration. The detailed descriptions of the connection variables assist in understanding how to optimize your configuration.

Connection pooling for HTTP client performance

This link provides information on connection pooling in CICS. 

Tuning Websphere Liberty

Modifying attributes of the server.xml file can modified to achieve better performance. Primarily, administrators should pay attention to the JVM parameters, including the heap size, maxPoolSize, and numConnectionsPerThreadLocal. Additionally, the JCM can be configured to allow for certain features such as hardware cryptography support, WLM, and SMF Type 120 diagnostic information. 

Resolving performance problems in IBM z/OS Connect OpenAPI 3

Since z/OS Connect runs on Liberty, we can utilize Liberty tools to analyze performance. This page can direct you to the Liberty ‘Troubleshooting performance issues’ documentation page and provides brief overview of processing hangs or waits as well as the allowCustomCacheKey setting in openidConnectClient configuration.

Using AT-TLS with z/OS Connect (OpenAPI 2)

Instead of implementing TLS in IBM z/OS Connect, AT-TLS provides encryption and decryption of data based on policy statements that are coded in the Policy Agent. This link provides more information on this security option that is available to you. 

z/OS Communications Server TCP/IP Performance

This link includes a few things to look at when you experience performance issues with z/OS Communications Server TCP/IP.