Intel Itanium
Intel Itanium (also called IA64[1], IA-64[2], I64[3], PA-WW[4] and IPF[5]) is a 64-bit processor architecture and corresponding processor family created by HP and Intel during the 90s and first released in 2001. Shipping with a significant delay, Itanium achieved moderate success between years 2002 and 2006, then slowly faded into obscurity, only kept alive for HP's Integrity platform running HP-UX, before it was finally discontinued in 2021[6]. Its most prominent feature is the use of VLIW-like explicit parallelism (EPIC), where the compiler selects which instructions should be run in parallel (instead of the CPU itself, as is common in RISC).
In the late 90s, Itanium was believed to be a revolutionary concept that will take over most areas on computing; because of that, many hardware and software vendors planned to support it, often abandoning their original architecture and porting their operating system to Itanium. These include IBM, SGI, DEC/Compaq, Bull, HP, SuperMicro, Sun, Dell, Tandem and Secure64. This led to Itanium being viewed by some as an unfortunate mistake that killed most RISC platforms[7] or even a conspiracy by Intel.
Itanium CPUs can be generally divided into three generations: Itanium 1, Itanium 2 and Itanium 9xxx. The 2001 Itanium 1, codenamed Merced, didn't deliver the expected performance - not many machines were made before it being replaced with Itanium 2 a year later. Itanium 2, codenamed McKinley, caught up and was adopted by many vendors including IBM, Dell and SGI, but that didn't last very long. By the release of the first 9xxx CPU, codenamed Montecito, Itanium became an HP-only architecture.
History
From Merced to Kittson.
Operating systems
Itanium-based systems support HP-UX (version 11.20 and higher), OpenVMS (8.0 and higher), Linux and SourceT Micro OS. In the past, it also supported Windows (from XP to Server 2008 R2), FreeBSD (from 5.0 to 10.4), NonStop OS and AIX (version 5L, also known by its codename Monterey). Unlike x86, Itanium support both big endian and little endian mode, which is used by many operating systems to keep their endianness the same as on other platforms. An exception to this is AIX, which is little endian on Itanium.
Compilers
GCC, MSVC, Open64, HP C (DEC), HP C/aCC, Intel C Compiler. Performance. Java.
Virtualization
On HP-UX, HP provides a hypervisor called Integrity Software Machines (also HPVM), capable of running HP-UX, and for older versions also Linux, Windows and OpenVMS. On Linux, KVM and Xen are supported, but both were removed eventually, hence you need an older kernel for them.
The capabilities of virtualization on Itanium depend on whether your CPU has VT-I or not. Without VT-i, you can run Linux, Windows and HP-UX in HPVM, and Linux in Xen PV (only older versions with PV guest support). VT-i gives you in addition OpenVMS support on HPVM, together with KVM and Xen HV on Linux.
RHEL 5 can be easily used for both PV and HV Xen:
# subscription-manager repos --enable=rhel-5-server-vt-rpms
# subscription-manager repos --enable=rhel-5-server-supplementary-rpms
# yum install xen kernel-xen virt-manager libvirt libvirt-python python-virtinst xen-ia64-guest-firmwareEmulators
Ski, QEMU, Simics.
References
- ↑ https://learn.microsoft.com/cs-cz/dotnet/api/microsoft.build.utilities.processorarchitecture.ia64
- ↑ https://www.pcmag.com/encyclopedia/term/ia-64
- ↑ https://support.hpe.com/hpesc/public/home/productSelector?psiTask=mostViewed&sp4ts.oid=5223226
- ↑ https://secure64.com/2021/01/06/bill-worley-technical-visionary-and-co-founder-of-secure64-has-passed-away/
- ↑ https://ipf-orc.sourceforge.net/
- ↑ https://www.techradar.com/news/intel-bids-farewell-to-itanium-processor-family
- ↑ https://www.pcmag.com/archive/how-the-itanium-killed-the-computer-industry-236394