IBM 4.6 manual IBM WebSphere Application Server, Java virtual machine JVM size

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2 IBM WebSphere Application Server

Regardless of the installation type (single server or cluster), the IBM Tivoli Identity Manager server can be thought of as two components: WebSphere Application Server (the J2EE application server running the application) and the IBM Tivoli Identity Manager application itself. Both components need to be tuned.

WebSphere Application Server allows you to use a variety of settings to tune your environment. This document discusses the timeouts and Java Messaging Service (JMS) queue endpoints.

2.1Java virtual machine (JVM) size

By default, WebSphere Application Server sets the maximum JVM size to 256 MB. This value is too small for the IBM Tivoli Identity Manager product to run beyond a basic concept test and should be increased to a minimum of 768 MB. If your server has adequate available RAM increase this value to as much as 1.5 GB. For large reconciliations or role and policy evaluations, the default values will not be enough memory to complete these tasks.

The maximum JVM size is not the actual maximum allocated size of the Java heap – as much as 15% is allocated to a portion of the heap for the system’s use. IBM recommends that you not use a value higher than 1.5 GB even if your system has the available memory.

Do not set the JVM heap size to be larger than the physical RAM. The WebSphere Application Server suffers significant performance degradation if the operating system swaps out the JVM to swap space. Consequences of this include very slow user interface (UI) performance, transaction roll backs, timeouts, and high disk utilization.

Determining the values

initial_jvm_heap_size – The initial size of the JVM heap in megabytes. Recommended value: 256 MB.

max_jvm_heap_size – The maximum size of the JVM heap in megabytes. Recommended value: 768 MB.

Setting the values

1)Open the Administration Console.

2)Expand the Servers list in the navigation pane.

3)Select Application Servers in the navigation pane.

4)Select the server to manage.

5)Select Process Definition from the Additional Properties pane at the bottom.

6)Select Java Virtual Machine from the Additional Properties pane at the bottom.

7)Set the Initial Heap Size to initial_jvm_heap_size.

8)Set the Maximum Heap Size to max_jvm_heap_size.

9)Repeat this procedure for each IBM Tivoli Identity Manager server.

Stop and restart each Application Server for these changes to take effect.

2.2Workload management (WLM) timeout

The WebSphere Application Server on z/OS provides a timeout value for how long it should wait for IIOP requests to complete. WebSphere Application Server uses the workload management (WLM) timeout value to terminate hung threads thereby preventing the hung thread from holding onto resources needed

IBM Tivoli Identity Manager Performance Tuning Guide

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Contents Issue Date Trademarks Copyright NoticeTable of contents Who should use this guide About this guideResource allocation Vital tuningsInitial tunings Introduction2 CPU MemoryDisk space IBM WebSphere Application Server Workload management WLM timeoutJava virtual machine JVM size Change WLM timeout to wlmtimeout Message driven bean MDB request timeoutTransaction timeout Select Container Services Select ORB ServiceSetting the values Threads IBM Tivoli Identity Manager applicationRecycle bin ReconciliationsSelect Reconciliation Limiting attributes returned from the adapterLimiting the attributes evaluated Maximum durationSet the Max Duration to maxduration Microsoft Active Directory IBM Tivoli Identity Manager adaptersDetermining the values JCL location Description Idle thread timeoutAPARs Buffer poolsActive log duplexing Locks per user limitReorg and Runstats Additional Zparms Default value Recommended valueCache sizes IBM Ldap ServerMax connections Runstats Changelog limitsRow locking on Searchts IndexingBest practices Regular maintenance Other resources

4.6 specifications

IBM 4.6, known for its robust and versatile capabilities, represents a significant evolution in the realm of enterprise software solutions. This version is primarily associated with IBM's middleware offerings, notably IBM WebSphere Application Server. It is engineered to support the development, deployment, and management of web applications with a focus on scalability, reliability, and security.

One of the standout features of IBM 4.6 is its enhanced performance optimizations. The platform employs advanced caching strategies and efficient resource management to improve application response times and throughput. This means that businesses can handle heavier loads with fewer resources, making it an economical choice for enterprises of all sizes.

Another notable characteristic is its support for a wide range of programming models and standards, including Java EE. This allows developers to build applications using familiar tools and frameworks, accelerating development timelines and improving productivity. Additionally, IBM 4.6 offers robust integration capabilities with existing enterprise systems through its support for web services and messaging protocols.

IBM 4.6 also emphasizes security. It includes features such as role-based access control, data encryption, and comprehensive auditing capabilities. These measures help organizations safeguard sensitive information and comply with various regulatory requirements.

The compatibility with multiple platforms, including cloud environments, is another significant advantage. IBM 4.6 simplifies deployment across diverse infrastructures, enabling businesses to operate in hybrid environments seamlessly. This flexibility is particularly beneficial as organizations increasingly adopt cloud migration strategies.

Furthermore, IBM 4.6 is equipped with a range of monitoring and management tools. These tools provide insights into application performance and health, allowing IT teams to proactively identify and address potential issues before they impact users. This capability is critical in maintaining high availability and reliability of services.

In summary, IBM 4.6 stands out as a comprehensive solution for enterprise application development and management. Its key features, such as enhanced performance, support for industry standards, strong security measures, platform compatibility, and monitoring tools, make it a compelling choice for organizations seeking to modernize their IT infrastructure. Implementing IBM 4.6 can empower businesses to innovate faster while ensuring their applications remain secure and efficient in a rapidly evolving digital landscape.
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