Complete the following tasks to eliminate system bottlenecks:
If the CPU usage is more than 80%, check the number of concurrent running tasks. Consider changing the load or using a grid to distribute tasks to different nodes. If you cannot reduce the load, consider adding more processors.
If swapping occurs, increase the physical memory or reduce the number of memory-intensive applications on the disk.
If you have excessive memory pressure (thrashing), consider adding more physical memory.
If the percent of time is high, tune the cache for PowerCenter to use in-memory cache instead of writing to disk. If you tune the cache, requests are still in queue, and the disk busy percentage is at least 50%, add another disk device or upgrade to a faster disk device. You can also use a separate disk for each partition in the session.
If physical disk queue length is greater than two, consider adding another disk device or upgrading the disk device. You also can use separate disks for the reader, writer, and transformation threads.
Consider improving network bandwidth.
When you tune UNIX systems, tune the server for a major database system.
If the percent time spent waiting on I/O (%wio) is high, consider using other under-utilized disks. For example, if the source data, target data, lookup, rank, and aggregate cache files are all on the same disk, consider putting them on different disks.