“After more than six years of effort, Intel is finally ready to
deploy its first processor based on the IA-64 instruction set,
which it co-developed with Hewlett-Packard. The chip, named
Itanium, is designed to go where no Pentium has gone before: the
high end of the server market. When it arrives, Itanium will
open doors not just for Intel but also for Linux. Today, a few
large companies ship the vast majority of big servers. Sun, HP, IBM
and Compaq servers rely mainly on proprietary RISC processors and
proprietary versions of UNIX. But with the turbo-charged Itanium,
many other vendors will deliver servers that match the power of
these proprietary machines. These vendors are likely to rely on
Linux or one of two key competitors: Monterey UNIX or Windows
2000.”
“Instead of simply extending the aging x86 instruction set to 64
bits, Intel decided to leap to a new instruction set, IA-64. This
state-of-the-art design includes a host of performance-enhancing
features–such as predication, speculation and register
frames–that are not found in x86 or RISC processors.”
“The general intent of these features is to give the compiler
more control over the hardware. In theory, the compiler can make
better decisions about how to group and order instructions for
optimal performance. Furthermore, the processor hardware is
simplified by relying on the compiler to make these decisions.
Simpler processors can be both faster and less expensive to
manufacture. Many previous instruction sets have failed to gain
significant market share. The problem has been incompatibility with
existing software. Itanium solves this problem by including an x86
translation unit on the chip. This unit can process any existing
x86 application, albeit at a lower speed than an application that
has been recompiled for IA-64.”