Definition of Parallel Processing

SAS 9 supports a new wave of SAS functionality related to parallel processing. Parallel processing refers to processing that is handled by multiple CPUs simultaneously. This technology takes advantage of hardware that has multiple CPUs, called SMP computers, and provides performance gains for two types of SAS processes:
  • threaded I/O
  • threaded application processing
SMP computers have multiple CPUs and an operating environment that can spawn and manage multiple pieces of executable code called threads. A thread is a single, independent flow of control through a program or within a process. Threading takes advantage of multiple CPUs by dividing processing among the available CPUs. A thread-enabled operating environment provides support for threads. For example, each thread needs a context (like a register set and a program counter), a segment of code to execute, and a piece of memory to use in the process.
Even if your site does not use an SMP computer, SAS 9 can still provide increased performance. Some types of threading can be performed using a single CPU.