# Compiler Testing & Masking

A majority of the test profiles provided by OpenBenchmarking.org to the Phoronix Test Suite are source-based tests. Relying upon the upstream source-code for each program under test allows for the tests to be easily brought to new platforms and architectures, avoids any out-of-tree / non-default packaging differences by different distributions and operating systems, and to allow the Phoronix Test Suite user to easily test new compilers and/or compiler options. For the source-based tests, the Phoronix Test Suite relies upon a compiler (e.g. GCC, LLVM/Clang, Sun Studio, Open64, et al) being present on the system under test. The Phoronix Test Suite does respect CC/CXX environment variables and test profiles are expected to honor CFLAGS/CXXFLAGS and other compiler settings.

The Phoronix Test Suite utilizes a compiler masking method for logging compiler options and other settings with each test profile installation. Prior to installing an open-source test, the Phoronix Test Suite determines the intended compiler to be used based upon the pre-set environment variables or the pre-set compiler(s) within the PATH environment variable. The Phoronix Test Suite then masks the compiler to ensure that any options/flags submitted to the compiler are first passed through pts-core so that they can be logged for later use, then is linked to the original, intended compiler. Additionally, other compiler binary names of the same type are blacklisted to prevent their un-intended use (i.e. if a test profile has hard-coded gcc in its build script, but clang is set as the compiler via CC, a sym-link will automatically be created from gcc to the masked clang for the duration of its test installation).

The logged compiler data is then used by the Phoronix Test Suite following the test execution process for automated result analysis. If there is a detected change in compiler settings, the differences are automatically reported to the test result graphs. Additionally, key compiler information (e.g. the compiler optimization level and key libraries that were linked at compile-time) is reported as a footnote on result graphs. The Phoronix Test Suite handles all of this in a fully automated manner; test profiles require no changes to take advantage of these compiler-reporting capabilities.

Separately, the Phoronix Test Suite attempts to automatically log the system compiler's build configuration (i.e. GCC's gcc -v "Configured with") output. If the Phoronix Test Suite detects there is a compiler build configuration change between test runs in a result file, it will report each compiler's build configuration to the system information table within the results viewer. Reported to the table is a reduced view of the build configuration options, with less relevant items being stripped away from this view to reduce verbosity. Upon clicking the text, the raw compiler information output can be viewed in full.

# Disk / File-System Testing

By default tests are installed to ~/.phoronix-test-suite/installed-tests/. However, the location can be updated from ~/.phoronix-test-suite/user-config.xml or dynamically via the PTS_TEST_INSTALL_ROOT_PATH environment variable.

When any disk tests are executed, the Phoronix Test Suite will attempt to log the mount options and scheduler of the disk/partition being used for testing. This information is subsequently displayed within the system information table. If the scheduler / mount options are maintained the same throughout all test runs, only a single line is displayed otherwise the options for each test run will be automatically displayed. The file-system in use is always captured and shown in the system information table.