Balancing the hardware resources

Use this task to improve the performance of long-running business processes, by balancing the hardware resources.

Why and when to perform this task

Before you start to tune the system, verify that the computer used is well balanced, so that the available CPU, memory, and disk space resources have the right relationship. A computer with fast CPUs, but low memory or low disk-access performance, is hard to tune.

Steps for this task

  1. Allocate enough disks.

    For long-running processes, good disk performance and multiple, fast disk drives are as important as a fast processor and a sufficient amount of memory.

    Separate disks provide independence of operation and are not affected by other operations. A striped RAID array distributes disk operations over several disks. This can provide improved performance over an equal number of single disks. Use a striped RAID array to overcome bottlenecks on single disks.

    For a system that runs long-running processes and does not use a RAID array, set up six or more disk drives, as follows:
    • One disk for the operating system and the swap space (page file on Windows®, paging space on AIX®, swap space on Solaris, paging space on HP-UX).
    • One disk for WebSphere® Application Server and its transaction log.
    • One disk for the transaction log of the message queuing system.
    • One disk for the persistent queue storage of the message queuing system.
    • One disk for the transaction log of the database management system.
    • One or more disks for the Business Process Choreographer database in the database management system. If more disks are available, distribute the INSTANCE tablespace on two or more disks.
  2. Allocate enough memory.
    The amount of memory to allocate depends on the platform:
    • For a Windows system with 3 GB of physical memory, a local database, and a local WebSphere MQ queue manager, use the following memory allocation:
      • 256 MB for Windows systems
      • 1024 MB for WebSphere Application Server
      • 256 MB for WebSphere MQ, if WebSphere MQ is used
      • 1.5 GB for the database
    • For an AIX system with 8 GB of physical memory, a local database, and local WebSphere MQ queue manager, use the following memory allocation:
      • 512 MB for AIX systems
      • 1024 MB for WebSphere Application Server
      • 512 MB for WebSphere MQ
      • 5 GB for the database
        Tip: To help ensure optimum performance, do not allocate all memory to the database, because the files you use and file caching, for example, also consume memory. Avoid situations in which data must be swapped to disk because insufficient high-speed memory is available.
    • For the application server, when running Business Process Choreographer, allocate more than the default amount of memory. Tuning the heap size of the application server is described in Tuning the application server.
  3. Move workload to other servers.

    Consider which applications or subsystems can be moved to other servers.

Result

Your computer hardware is now well balanced.

Terms of use |

Last updated: Thu Apr 27 14:54:57 2006

(c) Copyright IBM Corporation 2006.
This information center is powered by Eclipse technology (http://www.eclipse.org)