Each enhancement is intended to remove potential
bottlenecks that can limit performance. Unix and Linux are the most common
operating systems used in Oracle implementations on high-end SMP servers.
The number of CPUs possible in a SMP system is limited by scalability of the system
(memory) bus. As more CPUs are added to the bus, the bus itself can become saturated
with traffic between CPUs attached to the bus.
Systems featuring 64-bit CPUs can handle large amounts of data more efficiently
than previous 32-bit CPUs; they support dozens of CPUs on a single system with
hundreds of gigabytes of memory.
Of course, the database must have parallelization features to take full advantage of the
SMP architecture. Oracle operations such as query execution and other DML activity
and data loading can run as parallel processes within the Oracle server, allowing Oracle
to take advantage of the benefits of multiprocessor systems. Oracle, like all software
systems, benefits from parallel operations, as shown by ???Amdahl??™s Law.???
Total execution time = (parallel part / number of processors) + serial part
Amdahl??™s Law, formulated by mainframe pioneer Gene Amdahl in 1967 to describe
performance in mixed parallel and serial workloads, clearly shows that moving an
operation from the serial portion of execution to a parallel portion provides the performance
increases expected with the use of multiple processors.
Pages:
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643