To achieve the best performance, be sure to store your application binaries in the local stream file system.
It is much slower to start i5/OS™ PASE programs if your binaries (base program and libraries) are outside of the local stream file system because file mapping cannot be done.
If you run an application in i5/OS PASE that performs a large number of fork() operations, it will not run as fast as it runs on AIX®. This is because each i5/OS PASE fork() operation starts a new i5/OS job, which can have a significant impact on performance.
See the Performance topic in the System Management category for information about collecting and analyzing performance data.