The history of AIX

The history of AIX AIX (Advanced Interactive eXecutive) is IBM's homegrown UNIX operating system. AIX was first introduced by IBM in 1986. IBM ported AIX to its RS/6000® platform in 1989. The release of AIX Version 3 coincided with the announcement of the first RS/6000 models. The unique factor of these systems were that they outperformed all other machines in integer-compute performance and also by a factor of 10 in floating-point performance. Version 4 was introduced in 1994 and added support for symmetric multiprocessing (SMP) with the first RS/6000 SMP servers. The operating system continued to evolve until 1999, when AIX 4.3.3 introduced workload management (WLM). In May 2001, IBM unveiled AIX 5L, the L standing for "Linux affinity", which coincided with the release of its POWER4™ servers, which provided for the logical partitioning of servers. IBM created their first midrange hypervisor around this combination. More than any other factor, this was the breakthrough that IBM needed to challenge HP and SUN for UNIX supremacy. In just a few short years, IBM would dominate the market. In October of 2002, IBM announced dynamic logical partitioning (DLPAR) with AIX 5.2. AIX 5.3, introduced in August 2004, provided many new features: virtualization, security, reliability, systems management, and administration. Most importantly , AIX 5.3 fully supported the Advanced Power Virtualization (APV) capabilities of the POWER architecture; this included micropartioning, virtual I/O servers, and symmetric multithreading (SMT). IBM introduced AIX 6.1 in November 2007. Some of its major innovations include workload partitions (WPARs), similar to Solaris containers, and Live Application Mobility (not available with Solaris), which lets you move these partitions without application down time. AIX was the first operating system to introduce the idea of a journaling file system (JFS), an advance that enabled fast boot times by avoiding the need to perform file system checking (fsck) for disks on reboot. AIX also has a strong built-in Logical Volume Manager (LVM), introduced as early as 1990, which helps to partition and administer groups of disks. Another important innovation was the introduction of shared libraries, which avoided the need for an application to statically link to the libraries it used. The resulting smaller binaries used less of the hardware RAM to run and required less disk space for installation. Demonstrating their commitment to standards, the AIX OS was the first 64-bit UNIX OS to comply with the UNIX03 standard established by The Open Group and was the first operating system to support the UNIX 1998 standard. AIX has also included support for TCP/IP V6 since 1997, and was awarded the "Ready for IPv6" certification in 2006. Figure 2 shows the historical timeline for the evolution of AIX. Figure 2. The evolution of AIX Back to top Power Systems and AIX -- The undisputed UNIX leader in 2010 AIX celebrated its own major anniversary, its 20th anniversary in January 2006, and it appears to have an extremely bright future in the UNIX space. IBM's AIX has been the only UNIX flavor that increased its market share through the years, and IBM continues to own the market space for UNIX servers. Most of the UNIX growth at this time stems from IBM. AIX has benefited from the many hardware innovations that the POWER platform has introduced through the continues to do so. It has also benefited from its virtualization engine - PowerVM™. Why AIX? Performance, innovation, virtualization, availability, and a consistent roadmap In a recent study on OS reliability, polling users from 27 countries, IBM's AIX led all server operating systems for downtime - approximately 30 minutes per server of downtime, per year. This has to do with AIX near Continuous Availability features. During the early 1990's, there were five different RISC architectures that were actively competing with one another. IBM partnered with Apple and Motorola to come up with a common architecture, which would meet the standards of the alliance (A High-Performance Architecture with a History, 2006). Its first design was very simple and all instructions were completed in one clock cycle. It lacked floating point and parallel processing ability. The Power architecture was an attempt to correct this flaw. It consisted of over 100 instructions and was known as a complex RISC system. The Power1 chip consisted of 800,000 transistors per chip and was functional partitioned. It had separate floating point registers and could scale from the low- to the high-end workstations. The first chip actually had several chips on one single motherboard, but was refined to one RISC chip with more than 1 million transistors. It was used as the CPU for the Mars Pathfinder mission. While there were many other designs through the 1990's, it is true that the 1990's had mixed results for UNIX, as it lagged behind HP, Sun and other vendors. IBM has made substantial improvements throughout the years on their IBM proprietary RISC-based hardware, where additional mainframe-type components are actually needed today to utilize the new architecture. Systems like the HMC (hardware management console) and the Hypervisor (software which runs on hardware machines and manages one or more operating systems) are important elements of the Power architecture. The POWER5™ architecture, introduced in 2003, contained 276 million transistors per processor. It was based on the 130 nanometer copper/SOI Process and featured chip multiprocessing, a larger cache, a memory controller on the chip, simultaneous multi-threading (SMT), advanced power management, and improved hypervisor technology. The POWER6®, with approximately 790 million transistors, debuted in June 2007. Its dual-core design enabled it to reach 4.7 GHz. Innovations in energy and cooling let it retain the same power consumption as the POWER5, while almost doubling performance. The POWER6 has hardware support for decimal arithmetic. It also has the first decimal floating-point unit integrated in silicon. Several important PowerVM Virtualization enhancements were also released with the POWER6, including Live Partition Mobility, Decimal Floating Point, and Dynamic Energy Management. The Power6 5.00 GHz processor, based on the Power 595 simply is the fastest system UNIX server in existence. The 64-core server outperforms the 128-core HP Integrity Superdome with more performance at one-half the amount of cores. The 595 also has 90% of the performance of the 256-core Sun SPARC Enterprise M9000 and 90% of the performance with one-quarter of the cores. Power systems are based on mainframe-inspired reliability, availability, and serviceability (RAS) features such as First Failure Data Capture. This capability was also extended with introduction of the POWER6 processor-based servers to include Processor Instruction Retry, Alternate Processor Recovery, Partition Availability priority, Live Application Mobility, and Live Partition Mobility. All these features are designed to help enable you to eliminate systems-related planned and unplanned outages. If you need to take a system down for reconfiguration, firmware updates, or another reason, you will have the option of moving your applications to a different server without any impact to production operation. No reboots, no restarts, no service interruption, just continued outstanding service to your users. How does AIX itself work with hardware to prevent outages? One example is storage keys. This new capability exploits the POWER6 hardware to provide additional isolation of kernel and application data. It prevents invalid changes to memory caused by programming errors. Application use of POWER6 storage keys are enabled in AIX 5.3 and the AIX kernel. The AIX kernel exploitation of POWER6 keys is included in AIX 6.1. IBM is widely recognized as having the best virtualization product on the midrange, PowerVM. Some recent innovations include live application mobility (allowing one to fail over working partitions without downtime), Active Memory Sharing, and multiple shared processor pools. No other flavor of UNIX can boast these virtualization characteristics, nor can they match IBM's 40-year history of virtualization (PowerVM has evolved from mainframe/System z virtualization). AIX runs only on IBM Power Systems, easily the most powerful of midrange UNIX servers. IBM sells the fact that AIX runs exclusively on Power as a plus because it is fully optimized on this architecture and it has a clear road map around which the company adheres to religiously. AIX has always had an integrated logical volume manager, unlike other flavors that require add-on products. Back to top Summary AIX is the only flavor of UNIX that has continued to grow market share in recent years, partly because of the capabilities of its Power hardware that continues to lead the field in reliability, availability, and scalability. It is clear that IBM is at the forefront of UNIX innovation today and unquestionably the future of UNIX stands to stay bright because of its flagship UNIX flavor, AIX.