Frequently Asked Questions Q: What is Symmetrical Multi-Processing?A:
If the operating system being used supports symmetrical multi-processing (SMP), you can gain the additional performance boost of adding a second CPU to the system. SMP allows several processors to work simultaneously in the same operating system to service interrupts, access system memory, and perform I/O operations. Each time an instruction is received, it is processed by the CPU that is available at that moment. In this way processing time is reduced, which greatly improves system performance.
To get the most out of SMP, applications must support multi-threading. Multi-threading means that the software performs many of its operations in parallel. It accomplishes this by beginning a new "thread" to perform a group of related operations while the main portion of the program continues, without waiting for the results of the thread. With two processors installed, a thread can begin on one processor while the second processor continues executing the main program. The more a program uses threads, the more performance boost the system gets from having multiple processors installed. Conversely, if the program is written as a single thread of operation, it will not receive as much benefit from having multiple processors installed. If you are not sure whether or not your application is multi-threaded, contact the software manufacturer.
The Pentium Pro® and Pentium II® processors featured in this system are designed to support 32-bit operating systems and applications. To ensure optimum system performance, use only 32-bit programs on the NS-7000. Pentium Pro and Pentium II processors were designed to directly support the interconnection of multiple processors. Each processor contains all the logic required to work in multiprocessor configuration.
The Pentium Pro and Pentium II processors also feature an L2 cache, either integrated on the chip (Pentium Pro) or mounted on the SEC cartridge (Pentium II) to improve performance and to simplify system design. The L2 cache is non-blocking, which means that the processor can keep processing other instructions even if it doesn’t have the necessary data in the L2 cache. The L2 cache is also located on a separate "backside" bus which allows simultaneous access to both the L2 cache and main memory.