5.1. Installation phase

This phase was not concerned with the TenDRA technology, so it did not produce any noteworthy results.

5.2. NAT-NAT phase

The objective of this phase was to check that the system can be completely built with the native system compiler from the source delivery. Indeed, this phase was very helpful to set-up the build environment, and to evaluate the resources we would need for the next phases.

5.3. DRA-NAT phase

DRA-NAT build

During this phase we compiled the whole system, as for the NAT-NAT build, using the TenDRA technology as a standard compiler. Therefore, we used the system header files instead of the architecture neutral headers. At completion of this task, we obtained the following results:

• 65% of the library source files could be successfully compiled with the TenDRA technology.

• About 65% of the kernel C code could be successfully compiled with the TenDRA technology.

• Nearly all the commands and tools could be compiled with the TenDRA technology.

These figures need some explanation to see why the TenDRA technology failed to compile some of the files. There were essentially three cases where the technology could not compile the files:

• support of assembly language instructions inlined in C programs.

  Such code is not per-se architecture neutral and it is therefore clearly beyond the TenDRA technology goals.

  Assembly code was present in only 2% of the library source files, but was used in 22% of the files for the kernel components.

• support of special alignments for fields in structures (#pragma pack(n) directive)

  This feature was only relevant for Intel386 architecture. It was present in about 33% of the library C source files (Mostly for the Netware related libraries) and in 12% of the kernel C source files.

• Code written in C++ language.

  There were also some parts of the system which used the C++ language. Since a C++ producer is not yet available for the TenDRA technology, we could not compile these files.

  Files with C++ code represented about 9% of the source code for the libraries and about 5% of the source code for the commands.

In summary, excluding the C++ files, about 85% of the C source files could be successfully compiled with the TenDRA technology.

Apart from these issues, we found very few problems in the TenDRA compiler, 8 problems in fact, which were usually fixed or bypassed very quickly. These are included in the Appendix.

DRA-NAT validation

The DRA-NAT built kernel was customized for actual hardware and successfully booted.

The VSX4 tests have been built and exercised first on the native UNIX version. On this beta release, approximately 6,000 tests are successful while a hundred of them are not. Three libraries are involved (libc being the most important one), and best results are got using the shared version of them.

The following system software configuration was then used for recompiling and rerunning the VSX4 tests:

• TenDRA compiler in DRA-NAT mode

• DRA-NAT commands

• DRA-NAT libraries for compile-time link-edits

• DRA-NAT version of dynamically-linked libc at runtime.

• DRA-NAT kernel

With this configuration, the VSX4 tests level of success is the same as for the native system. Two modules of the dynamically linked libc library were temporarily replaced by their native version in order to cure problems with the sed command.

The AIMIII benchmark was used to exercise the native and DRA-NAT systems. At a medium user load level (simulated by the benchmark), i.e. 30-60 users, the performance of the two systems is similar: variations are below 3%.

During the DRA-NAT validation phase, only 7 problems in TenDRA technology were encountered. These are included in the Appendix.

5.4. DRA-DRA phase

A base API has been created from a merge between the svid3 and xpg4 APIs, which are included in the TenDRA technology delivery. This allowed us to compile 57 commands (out of approximately 600). This demonstrated the need for a custom extension API for compiling most UnixWare commands. With the present extension API, 46 additional commands have been compiled.

During this phase, two minor problems in the TenDRA technology were identified (these are included in the Appendix).