Hardware sizing and tuning

Product Master is a Java™ Platform, Enterprise Edition application where RAM and processor performance are more important than, for example, disk access speed.

Allocating the hardware

Allocating the correct hardware is critical for sustained performance of the solution. The correct size of the hardware that is required to effectively run the final solution depends on the volume of the activity on the system and the overall complexity of the solution. Correct sizing can be done by working with the technical sales team, IBM® services team, or the performance team.

System memory

Ensure that there is sufficient physical memory available so no memory swapping and paging occurs. On an environment that runs Product Master services, make sure that all services -Xmx settings account in the maximum (total physical memory - 1.5 GB).

For more information, see Configuring memory flags for each service type.

Tuning

Correctly sized hardware is only effective when it is properly tuned. There are a few key areas that commonly appear as the cause of performance problems:
  • Latency and bandwidth between the application server and database. The latency should be under 0.25 ms between the application server and the database. This can be measured by using the traceroute command on most systems. The connection between the two should be a gigabit Ethernet capable of transferring large files at 25 MB/s through FTP.
  • Number of open descriptors is too low. Unexpected problems can be avoided by checking the number open descriptors and verifying that they are set according to WebSphere® Application Server guidelines to 8000. Number of open descriptors can be checked by using the ulimit –a on most computers, and can be reset by using the ulimit –n.
    Note: The ulimit displays the settings per user for the logged-in user.

File system

Although Product Master does not create a high demand on the disk, a separate file system is recommended. A separate file system might not affect performance greatly, but it does separate the system data and log files from other files on the system and improves disk space administration. A file system for the document store and another file system for the log files is recommended.

Product Master does not make heavy use of the disk for the subsystem in local installations, so nearly any disk configuration should suffice, whether it is single-disk, spanning, or RAID arrays.

Use at least fast Ethernet links (Gigabit) between the database and application servers. In a clustered installation, fast Ethernet between the application servers and the NFS server are a minimum, as is a well-tuned and suitably sized NFS server.

Load balancing and failover

The proper configuration of any application is to balance the load and allow for failover in case of unexpected problems. An easy way to address potential overloading of the application server is to use a load balancer. Multiple instances of the scheduler can be started on one or more servers and various services of the scheduler load balance themselves automatically.

Processor

You should obtain the fastest processor and the most memory affordable. Multiprocessor systems improve performance greatly, and a system for your services with less than 8 GB of memory should not be considered for most applications. A dual-processor dual-core system and at least 8 GB of RAM is recommended.