TNS/E Native Application Conversion Guide

Developing a Conversion Strategy
TNS/E Native Application Conversion Guide—529659-003
2-2
Preparing Programs for Conversion
You can use the Measure system performance-analysis tool to determine which
programs can be significantly improved by native-compiling. When measuring program
performance, select a measurement window that coincides with some representative
portion of the system workload, usually the system’s peak time. For further verification,
take and compare multiple measurements to create a level of confidence with the data
collected.
Another issue to consider when converting to native mode is the effort required to
convert the program. It is not a trivial matter to convert programs that rely significantly
on TNS hardware and process architecture. For example, a program that explicitly
manipulates the P-register probably requires significant changes to convert to native
mode.
Preparing Programs for Conversion
If you are migrating your TNS programs from a TNS/R system, you must complete
these tasks before converting a program to native mode:
•
Compile programs with a D20 or later TNS compiler version and resolve any
C-series to D-series conversion issues.
•
Run your programs successfully on a system running the current version of the
operating system and resolve any migration issues.
•
Run your program successfully on an Itanium-based NonStop system and resolve
any hardware variances between TNS and TNS/E systems. For information on
hardware variances, see the Object Code Accelerator (OCA) Manual . For general
information on migrating a Guardian TNS program to a TNS/E system, see the H-
Series Application Migration Guide .
•
Convert your C or C++ program to use the 32-bit or wide data model if it does not
do so already. For details, see Converting Code to Use 32-Bit Pointers and
Integers on page 3-3.
This manual assumes that you have completed these tasks. For information on
C-series to D-series migration, see:
•
Guardian Application Conversion Guide
•
D-Series System Migration Planning Guide
Planning System Resources
In general, native object files use the same or slightly fewer disk resources than
accelerated object files (object files produced by a TNS compiler and processed by the
accelerator or OCA). Likewise, native processes use comparable processor memory to
TNS processes running in accelerated mode.
The TNS/E native environment is available only on systems running H-series versions
of the operating system. These systems include the NonStop NS-series servers.