16.2 Dependency Classes

Because Oracle Linux and DTrace support a variety of operating platforms and processors, DTrace also labels interfaces with a dependency class, which indicates whether an interface is common to all Oracle Linux platforms and processors or whether the interface is associated with a particular system architecture. The dependency class is orthogonal to the stability levels previously described in this document. For example, a DTrace interface can be Stable, but only supported on x86_64 microprocessors. Or, the interface can be Unstable, but common to all Oracle Linux platforms. The DTrace dependency classes are described in the following table and listed in order, from least common (most specific to a particular architecture), to most common (common to all architectures).

Dependency Class

Description

Unknown

The interface has an unknown set of architectural dependencies. DTrace does not necessarily know the architectural dependencies of all entities, such as the data types defined in the operating system implementation. The Unknown label is typically applied to interfaces of very low stability for which dependencies cannot be computed. The interface might not be available when using DTrace on any architecture other than what you are currently using.

CPU

The interface is specific to the CPU model of the current system. Interfaces with CPU model dependencies might not be available on other CPU implementations, even if those CPUs export the same instruction set architecture (ISA).

Platform

The interface is specific to the hardware platform for the current system. A platform typically associates a set of system components and architectural characteristics. To display the current platform name, use the uname -i command. The interface might not be available on other hardware platforms.

Group

The interface is specific to the hardware platform group for the current system. A platform group typically associates a set of platforms with related characteristics together under a single name. To display the current platform group name, use the uname -m command. The interface is available on other platforms in the platform group, but it might not be available on hardware platforms that are not members of the group.

ISA

The interface is specific to the ISA that is supported by the microprocessors on the current system. The ISA describes a specification for software that can be executed on the microprocessor, including details such as assembly language instructions and registers. To display the native instruction sets that are supported by the system, use the isainfo command. The interface might not be supported on systems that do not export any of the same instruction sets.

Common

The interface is common to all Oracle Linux platforms, regardless of the underlying hardware. DTrace programs and layered applications that depend only on Common interfaces can be executed and deployed on other Oracle Linux platforms with the same Oracle Linux and DTrace revisions. The majority of DTrace interfaces are Common, so you can use them wherever you use Oracle Linux.