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66-538: The PowerPC 970 , PowerPC 970FX , and PowerPC 970MP are 64-bit PowerPC CPUs from IBM introduced in 2002. Apple branded the 970 as PowerPC G5 for its Power Mac G5 . Having created the PowerPC architecture in the early 1990s via the AIM alliance , the 970 family was created through a further collaboration between IBM and Apple . The project was codenamed GP-UL or Giga Processor Ultra Light, where Giga Processor

132-409: A 32-bit to a 64-bit architecture is a fundamental alteration, as most operating systems must be extensively modified to take advantage of the new architecture, because that software has to manage the actual memory addressing hardware. Other software must also be ported to use the new abilities; older 32-bit software may be supported either by virtue of the 64-bit instruction set being a superset of

198-490: A file server , web server or run high-performance computing applications in clusters – a dedicated cluster Xserve, the Xserve Cluster Node, without a video card and optical drives was also available. The first Xserve had a PowerPC G4 processor, replaced by a PowerPC G5 in 2004, and by Intel Xeon processors in 2006; each was available in single-processor and dual-processor configurations. The Xserve

264-613: A virtual machine of a 16- or 32-bit operating system to run 16-bit applications or use one of the alternatives for NTVDM . Mac OS X 10.4 "Tiger" and Mac OS X 10.5 "Leopard" had only a 32-bit kernel, but they can run 64-bit user-mode code on 64-bit processors. Mac OS X 10.6 "Snow Leopard" had both 32- and 64-bit kernels, and, on most Macs, used the 32-bit kernel even on 64-bit processors. This allowed those Macs to support 64-bit processes while still supporting 32-bit device drivers; although not 64-bit drivers and performance advantages that can come with them. Mac OS X 10.7 "Lion" ran with

330-725: A 16  MiB ( 16 × 1024 bytes ) address space. 32-bit superminicomputers , such as the DEC VAX , became common in the 1970s, and 32-bit microprocessors, such as the Motorola 68000 family and the 32-bit members of the x86 family starting with the Intel 80386 , appeared in the mid-1980s, making 32 bits something of a de facto consensus as a convenient register size. A 32-bit address register meant that 2 addresses, or 4  GB of random-access memory (RAM), could be referenced. When these architectures were devised, 4 GB of memory

396-423: A 32- or 64-bit Java virtual machine with no modification. The lengths and precision of all the built-in types, such as char , short , int , long , float , and double , and the types that can be used as array indices, are specified by the standard and are not dependent on the underlying architecture. Java programs that run on a 64-bit Java virtual machine have access to a larger address space. Speed

462-609: A 64-bit kernel on more Macs, and OS X 10.8 "Mountain Lion" and later macOS releases only have a 64-bit kernel. On systems with 64-bit processors, both the 32- and 64-bit macOS kernels can run 32-bit user-mode code, and all versions of macOS up to macOS Mojave (10.14) include 32-bit versions of libraries that 32-bit applications would use, so 32-bit user-mode software for macOS will run on those systems. The 32-bit versions of libraries have been removed by Apple in macOS Catalina (10.15). Linux and most other Unix-like operating systems, and

528-544: A PowerBook G5 might be possible. However, several obstacles prevented even the 970FX from being used in this application. At 1.5 GHz, the G5 was not substantially faster than the 1.5 and 1.67 GHz G4 processors, which Apple used in PowerBooks instead. Furthermore, the northbridge chips available to interface the 970FX to memory and other devices were not designed for portable computers, and consumed too much power. Finally,

594-780: A driver for a 32-bit PCI device asking the device to DMA data into upper areas of a 64-bit machine's memory could not satisfy requests from the operating system to load data from the device to memory above the 4 gigabyte barrier, because the pointers for those addresses would not fit into the DMA registers of the device. This problem is solved by having the OS take the memory restrictions of the device into account when generating requests to drivers for DMA, or by using an input–output memory management unit (IOMMU). As of August 2023 , 64-bit architectures for which processors are being manufactured include: Most architectures of 64 bits that are derived from

660-449: A generation of computers in which 64-bit processors are the norm. 64 bits is a word size that defines certain classes of computer architecture, buses, memory, and CPUs and, by extension, the software that runs on them. 64-bit CPUs have been used in supercomputers since the 1970s ( Cray-1 , 1975) and in reduced instruction set computers (RISC) based workstations and servers since the early 1990s. In 2003, 64-bit CPUs were introduced to

726-484: A given process and can have implications for efficient processor cache use. Maintaining a partial 32-bit model is one way to handle this, and is in general reasonably effective. For example, the z/OS operating system takes this approach, requiring program code to reside in 31-bit address spaces (the high order bit is not used in address calculation on the underlying hardware platform) while data objects can optionally reside in 64-bit regions. Not all such applications require

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792-610: A hardware prefetch unit and a three way branch prediction unit . Like the POWER4, the front-end is nine stages long. The PowerPC 970 can fetch and decode up to eight instructions, dispatch up to five to reserve stations, issue up to eight to the execution units and retire up to five per cycle. The execution pipelines were lengthened compared to the POWER4 to achieve higher IPC . It has eight execution units: two arithmetic logic units (ALUs), two double-precision floating-point units , two load/store units and two AltiVec units. One of

858-751: A large address space or manipulate 64-bit data items, so these applications do not benefit from these features. x86-based 64-bit systems sometimes lack equivalents of software that is written for 32-bit architectures. The most severe problem in Microsoft Windows is incompatible device drivers for obsolete hardware. Most 32-bit application software can run on a 64-bit operating system in a compatibility mode , also termed an emulation mode, e.g., Microsoft WoW64 Technology for IA-64 and AMD64. The 64-bit Windows Native Mode driver environment runs atop 64-bit NTDLL.DLL , which cannot call 32-bit Win32 subsystem code (often devices whose actual hardware function

924-504: A maximum power usage of 75 W at 1.8 GHz and 100 W at 2.0 GHz. Each core has 1 MB of L2 cache , twice that of the 970FX. Like the 970FX, this chip was produced at the 90 nm process. When one of the cores is idle, it will enter a "doze" state and shut down. The 970MP also includes partitioning and virtualization features. The PowerPC 970MP replaced the PowerPC 970FX in Apple's high-end Power Mac G5 computers, while

990-521: A problem. 64-bit drivers were not provided for many older devices, which could consequently not be used in 64-bit systems. Driver compatibility was less of a problem with open-source drivers, as 32-bit ones could be modified for 64-bit use. Support for hardware made before early 2007, was problematic for open-source platforms, due to the relatively small number of users. 64-bit versions of Windows cannot run 16-bit software . However, most 32-bit applications will work well. 64-bit users are forced to install

1056-413: A processor with 64-bit memory addresses can directly access 2 bytes (16 exabytes or EB) of byte-addressable memory. With no further qualification, a 64-bit computer architecture generally has integer and addressing registers that are 64 bits wide, allowing direct support for 64-bit data types and addresses. However, a CPU might have external data buses or address buses with different sizes from

1122-405: A single integer register can store the memory address to any location in the computer's physical or virtual memory . Therefore, the total number of addresses to memory is often determined by the width of these registers. The IBM System/360 of the 1960s was an early 32-bit computer; it had 32-bit integer registers, although it only used the low order 24 bits of a word for addresses, resulting in

1188-856: A white ceramic substrate that was typical for IBM's high end processors of the era. The PowerPC 970 was announced by IBM in October 2002. It was released in Apple Computer 's Power Mac G5 in June 2003. Like its naming convention of G3 and G4, Apple branded the PowerPC 970 based products as G5, for the fifth generation of PowerPC. IBM released its first PowerPC 970 blade servers, the BladeCenter JS20 , in November 2003. The PowerPC 970 has 512 KB of full-speed L2 cache and clock speeds from 1.6 to 2.0 GHz. The front side bus runs at half

1254-522: Is an abbreviation of "Long, Pointer, 64". Other models are the ILP64 data model in which all three data types are 64 bits wide, and even the SILP64 model where short integers are also 64 bits wide. However, in most cases the modifications required are relatively minor and straightforward, and many well-written programs can simply be recompiled for the new environment with no changes. Another alternative

1320-483: Is emulated in user mode software, like Winprinters). Because 64-bit drivers for most devices were unavailable until early 2007 (Vista x64), using a 64-bit version of Windows was considered a challenge. However, the trend has since moved toward 64-bit computing, more so as memory prices dropped and the use of more than 4 GB of RAM increased. Most manufacturers started to provide both 32-bit and 64-bit drivers for new devices, so unavailability of 64-bit drivers ceased to be

1386-413: Is not the only factor to consider in comparing 32-bit and 64-bit processors. Applications such as multi-tasking, stress testing, and clustering – for high-performance computing (HPC) – may be more suited to a 64-bit architecture when deployed appropriately. For this reason, 64-bit clusters have been widely deployed in large organizations, such as IBM, HP, and Microsoft. Summary: A common misconception

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1452-441: Is often written with implicit assumptions about the widths of data types. C code should prefer ( u ) intptr_t instead of long when casting pointers into integer objects. A programming model is a choice made to suit a given compiler, and several can coexist on the same OS. However, the programming model chosen as the primary model for the OS application programming interface (API) typically dominates. Another consideration

1518-504: Is often, but not always, based on 64-bit units of data. For example, although the x86 / x87 architecture has instructions able to load and store 64-bit (and 32-bit) floating-point values in memory, the internal floating-point data and register format is 80 bits wide, while the general-purpose registers are 32 bits wide. In contrast, the 64-bit Alpha family uses a 64-bit floating-point data and register format, and 64-bit integer registers. Many computer instruction sets are designed so that

1584-418: Is that 64-bit architectures are no better than 32-bit architectures unless the computer has more than 4 GB of random-access memory . This is not entirely true: The main disadvantage of 64-bit architectures is that, relative to 32-bit architectures, the same data occupies more space in memory (due to longer pointers and possibly other types, and alignment padding). This increases the memory requirements of

1650-495: Is the IBM AS/400 , software for which is compiled into a virtual instruction set architecture (ISA) called Technology Independent Machine Interface (TIMI); TIMI code is then translated to native machine code by low-level software before being executed. The translation software is all that must be rewritten to move the full OS and all software to a new platform, as when IBM transitioned the native instruction set for AS/400 from

1716-507: Is the LLP64 model, which maintains compatibility with 32-bit code by leaving both int and long as 32-bit. LL refers to the long long integer type, which is at least 64 bits on all platforms, including 32-bit environments. There are also systems with 64-bit processors using an ILP32 data model, with the addition of 64-bit long long integers; this is also used on many platforms with 32-bit processors. This model reduces code size and

1782-598: Is the codename for the POWER4 from which the core was derived. When Apple introduced the Power Mac G5 , it stated that this was a five-year collaborative effort, with multi-generation roadmap. This forecast however was short-lived when Apple later had to retract its promise to deliver a 3 GHz processor only one year after its introduction. IBM was also unable to reduce power consumption to levels necessary for laptop computers. Ultimately, Apple only used three variants of

1848-400: Is the data model used for device drivers . Drivers make up the majority of the operating system code in most modern operating systems (although many may not be loaded when the operating system is running). Many drivers use pointers heavily to manipulate data, and in some cases have to load pointers of a certain size into the hardware they support for direct memory access (DMA). As an example,

1914-649: The Apple Watch Series 4 and 5. Many 64-bit platforms today use an LP64 model (including Solaris, AIX , HP-UX , Linux, macOS, BSD, and IBM z/OS). Microsoft Windows uses an LLP64 model. The disadvantage of the LP64 model is that storing a long into an int truncates. On the other hand, converting a pointer to a long will "work" in LP64. In the LLP64 model, the reverse is true. These are not problems which affect fully standard-compliant code, but code

1980-513: The C and C++ toolchains for them, have supported 64-bit processors for many years. Many applications and libraries for those platforms are open-source software , written in C and C++, so that if they are 64-bit-safe, they can be compiled into 64-bit versions. This source-based distribution model, with an emphasis on frequent releases, makes availability of application software for those operating systems less of an issue. In 32-bit programs, pointers and data types such as integers generally have

2046-464: The Cray-1 , used registers up to 64 bits wide, and supported 64-bit integer arithmetic, although they did not support 64-bit addressing. In the mid-1980s, Intel i860 development began culminating in a 1989 release; the i860 had 32-bit integer registers and 32-bit addressing, so it was not a fully 64-bit processor, although its graphics unit supported 64-bit integer arithmetic. However, 32 bits remained

PowerPC 970 - Misplaced Pages Continue

2112-963: The Nintendo 64 and the PlayStation 2 had 64-bit microprocessors before their introduction in personal computers. High-end printers, network equipment, and industrial computers also used 64-bit microprocessors, such as the Quantum Effect Devices R5000 . 64-bit computing started to trickle down to the personal computer desktop from 2003 onward, when some models in Apple 's Macintosh lines switched to PowerPC 970 processors (termed G5 by Apple), and Advanced Micro Devices (AMD) released its first 64-bit x86-64 processor. Physical memory eventually caught up with 32 bit limits. In 2023, laptop computers were commonly equipped with 16GB and servers up to 64 GB of memory, greatly exceeding

2178-582: The Worldwide Developers Conference on August 7, 2006, and are significantly faster compared to the Xserve G5. They use Intel Xeon (' Woodcrest ') processors, DDR2 ECC FB-DIMMs , ATI Radeon graphics, a maximum storage capacity of 2.25 TB when used with three 750 GB drives, optional redundant power supplies and a 1U rack form factor. The Intel Xserves now had on board video, freeing up an expansion slot. On January 8, 2008 Xserve

2244-513: The iMac G5 and the legacy PCI-X Power Mac G5 continued to use the PowerPC 970FX processor. The PowerPC 970MP is used in IBM's JS21 blade modules, IBM Intellistation POWER 185 workstation and YDL PowerStation by Fixstars Solutions (Yellow Dog Linux (YDL) PowerStation). Due to high power requirements, IBM discontinued units above 2.0 GHz. Two dedicated northbridges for PowerPC 970-based computers were manufactured by IBM: A CPC965 northbridge

2310-521: The 32-bit instruction set, so that processors that support the 64-bit instruction set can also run code for the 32-bit instruction set, or through software emulation , or by the actual implementation of a 32-bit processor core within the 64-bit processor, as with some Itanium processors from Intel, which included an IA-32 processor core to run 32-bit x86 applications. The operating systems for those 64-bit architectures generally support both 32-bit and 64-bit applications. One significant exception to this

2376-833: The 32-bit limit of 4 GB ( 4 × 1024 bytes ), allowing room for later expansion and incurring no overhead of translating full 64-bit addresses. The Power ISA v3.0 allows 64 bits for an effective address, mapped to a segmented address with between 65 and 78 bits allowed, for virtual memory, and, for any given processor, up to 60 bits for physical memory. The Oracle SPARC Architecture 2015 allows 64 bits for virtual memory and, for any given processor, between 40 and 56 bits for physical memory. The ARM AArch64 Virtual Memory System Architecture allows 48 bits for virtual memory and, for any given processor, from 32 to 48 bits for physical memory. The DEC Alpha specification requires minimum of 43 bits of virtual memory address space (8 TB) to be supported, and hardware need to check and trap if

2442-655: The 4 GB address capacity of 32 bits. In principle, a 64-bit microprocessor can address 16 EB ( 16 × 1024 = 2 = 18,446,744,073,709,551,616 bytes ) of memory. However, not all instruction sets, and not all processors implementing those instruction sets, support a full 64-bit virtual or physical address space. The x86-64 architecture (as of 2016 ) allows 48 bits for virtual memory and, for any given processor, up to 52 bits for physical memory. These limits allow memory sizes of 256  TB ( 256 × 1024 bytes ) and 4  PB ( 4 × 1024 bytes ), respectively. A PC cannot currently contain 4  petabytes of memory (due to

2508-575: The 970FX had inadequate power saving features for a portable CPU. Its minimum (idle) power was much too high, which would have led to poor battery life figures in a notebook computer. IBM announced the PowerPC 970MP , codenamed "Antares", on July 7, 2005, at the Power Everywhere forum in Tokyo. The 970MP is a dual-core derivative of the 970FX with clock speeds between 1.2 and 2.5 GHz, and

2574-546: The AltiVec units executes integer and floating-point instructions, and the other only permute instructions. The latter has three subunits for simple integer, complex integer and floating-point instructions. These units have pipelines of varying lengths: 10 stages for simple integer and permute instructions, 13 stages for complex integer instructions and 16 stage for floating-point instructions. The processor has two unidirectional 32-bit double data rate (DDR) buses (one for reads,

2640-754: The G4 cluster node) at US$ 2,999. On January 3, 2005, Apple updated the Xserve G5 with faster processors in the dual-processor configurations. 400 GB hard disks were made available for up to 1.2 TB of internal storage. The slot-loading optical drive was upgraded to a combination DVD-ROM/CD-RW standard, DVD-/+RW optional. Soon after, Apple updated the Xserve and Xserve RAID to allow the use of 500 GB Hard Drives. Xserve G5 models before April 2005 shipped with Mac OS X v10.3 "Panther", after April 2005 shipped with Mac OS X v10.4 "Tiger". According to Apple, all of these models are obsolete. The Intel-based Xserves were announced at

2706-1052: The Instruction Fetch Unit, 67 in the Instruction Decode Unit, 100 in the Functional Units, and 32 in the Store Queue. It has 64 KBs of directly mapped Instruction Cache and 32 KBs of D-Cache. Apple released 970FX-powered machines throughout 2004: the Xserve G5 in January, the Power Mac G5 in June, and the iMac G5 in August. The Power Mac introduced a top clock speed of 2.5 GHz while liquid-cooled (eventually reaching as high as 2.7 GHz in April 2005). The iMac ran

PowerPC 970 - Misplaced Pages Continue

2772-475: The Xserve. According to Apple, all of these models are obsolete. On January 6, 2004 Apple introduced the Xserve G5, a redesigned higher-performance Xserve. The 32-bit PowerPC G4s were replaced with one or two 64-bit PowerPC 970 processors running at 2 GHz. Ventilation issues restricted it to three SATA hot-swap drive bays, with the original space for the fourth drive bay used for air vents. The front plate and slot-loading optical drive were retained from

2838-460: The front side bus at a third of the clock speed. Market demand was intense for a faster laptop CPU than the G4, but Apple never delivered a G5 series CPU in PowerBook laptops. The original 970 uses far too much power and was never seriously viewed as a candidate for a portable computer. The 970FX reduced thermal design power (TDP) to about 30 W at 1.5 GHz, which led many users to believe

2904-458: The last Xserve G4. The higher memory capacity and bandwidth as well as the stronger floating-point performance of the PowerPC 970 made it more suitable for high-performance computing (HPC) applications. System X is one such cluster computer built with Xserves. Three configuration options were available: a single-processor model at US$ 2,999, a dual-processor model at $ 3,999, and a dual-processor cluster node model (with an unchanged appearance from

2970-631: The mainstream PC market in the form of x86-64 processors and the PowerPC G5 . A 64-bit register can hold any of 2 (over 18 quintillion or 1.8×10 ) different values. The range of integer values that can be stored in 64 bits depends on the integer representation used. With the two most common representations, the range is 0 through 18,446,744,073,709,551,615 (equal to 2 − 1) for representation as an ( unsigned ) binary number , and −9,223,372,036,854,775,808 (−2 ) through 9,223,372,036,854,775,807 (2 − 1) for representation as two's complement . Hence,

3036-475: The maximum storage capacity, bringing it to 6 TB when used with three 2 TB drives. An option to add a SSD boot-drive that does not occupy a drive bay was also implemented. The addition of the SSD boot drive allows all drives to be swapped whilst the server remains online. It is also Apple's first Xserve to use PVC-free internal cables and components and contain no brominated flame retardants. On August 28, 2009 Xserve

3102-493: The mid-1990s, HAL Computer Systems , Sun Microsystems , IBM , Silicon Graphics , and Hewlett-Packard had developed 64-bit architectures for their workstation and server systems. A notable exception to this trend were mainframes from IBM, which then used 32-bit data and 31-bit address sizes; the IBM mainframes did not include 64-bit processors until 2000. During the 1990s, several low-cost 64-bit microprocessors were used in consumer electronics and embedded applications. Notably,

3168-547: The modules. 64-bit From the software perspective, 64-bit computing means the use of machine code with 64-bit virtual memory addresses. However, not all 64-bit instruction sets support full 64-bit virtual memory addresses; x86-64 and AArch64 for example, support only 48 bits of virtual address, with the remaining 16 bits of the virtual address required to be all zeros (000...) or all ones (111...), and several 64-bit instruction sets support fewer than 64 bits of physical memory address. The term 64-bit also describes

3234-409: The norm until the early 1990s, when the continual reductions in the cost of memory led to installations with amounts of RAM approaching 4 GB, and the use of virtual memory spaces exceeding the 4 GB ceiling became desirable for handling certain types of problems. In response, MIPS and DEC developed 64-bit microprocessor architectures, initially for high-end workstation and server machines. By

3300-763: The older 32/48-bit IMPI to the newer 64-bit PowerPC-AS , codenamed Amazon . The IMPI instruction set was quite different from even 32-bit PowerPC, so this transition was even bigger than moving a given instruction set from 32 to 64 bits. On 64-bit hardware with x86-64 architecture (AMD64), most 32-bit operating systems and applications can run with no compatibility issues. While the larger address space of 64-bit architectures makes working with large data sets in applications such as digital video , scientific computing, and large databases easier, there has been considerable debate on whether they or their 32-bit compatibility modes will be faster than comparably priced 32-bit systems for other tasks. A compiled Java program can run on

3366-549: The other for writes) to the system controller chip ( northbridge ) running at one quarter of the processor core speed. The buses also carry addresses and control signals in addition to data so only a percentage of the peak bandwidth can be realized (6.4 GB/s at 450 MHz). As the buses are unidirectional, each direction can realize only half the aggregate bandwidth, or 3.2 GB/s. All generations of 970 processors were manufactured in IBM's East Fishkill plant in New York on

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3432-428: The other types of registers cannot. The size of these registers therefore normally limits the amount of directly addressable memory, even if there are registers, such as floating-point registers, that are wider. Most high performance 32-bit and 64-bit processors (some notable exceptions are older or embedded ARM architecture (ARM) and 32-bit MIPS architecture (MIPS) CPUs) have integrated floating point hardware, which

3498-420: The physical size of the memory chips), but AMD envisioned large servers, shared memory clusters, and other uses of physical address space that might approach this in the foreseeable future. Thus the 52-bit physical address provides ample room for expansion while not incurring the cost of implementing full 64-bit physical addresses. Similarly, the 48-bit virtual address space was designed to provide 65,536 (2 ) times

3564-485: The processor's clock speed. The PowerPC 970FX has a 90 nm manufacturing process and has a maximum power rating of 11 watts at 149 degrees Fahrenheit (65 °C) while clocked at 1 GHz and a maximum of 48 watts at 2 GHz. It has 10 functional units – 2 Fixed-Point Units, 2 Load/Store Units, 2 Floating Point Units, 1 Branch Unit, 1 SIMD ALU unit, 1 SIMD Permute unit, and 1 Condition Register. It supports up to 215 instructions in-flight: 16 in

3630-438: The processor. IBM's JS20/JS21 blade modules and some low-end workstations and System p servers are based on the PowerPC 970. It is also used in some high end embedded systems like Mercury 's Momentum XSA-200. IBM is also licensing the PowerPC 970 core for use in custom applications. The PowerPC 970 is a single core derivative of the POWER4 and can process both 32-bit and 64-bit PowerPC instructions natively. It has

3696-578: The registers, even larger (the 32-bit Pentium had a 64-bit data bus, for instance). Processor registers are typically divided into several groups: integer , floating-point , single instruction, multiple data (SIMD), control , and often special registers for address arithmetic which may have various uses and names such as address , index , or base registers . However, in modern designs, these functions are often performed by more general purpose integer registers. In most processors, only integer or address-registers can be used to address data in memory;

3762-547: The remaining unsupported bits are zero (to support compatibility on future processors). Alpha 21064 supported 43 bits of virtual memory address space (8 TB) and 34 bits of physical memory address space (16 GB). Alpha 21164 supported 43 bits of virtual memory address space (8 TB) and 40 bits of physical memory address space (1 TB). Alpha 21264 supported user-configurable 43 or 48 bits of virtual memory address space (8 TB or 256 TB) and 44 bits of physical memory address space (16 TB). A change from

3828-435: The same architecture of 32 bits can execute code written for the 32-bit versions natively, with no performance penalty. This kind of support is commonly called bi-arch support or more generally multi-arch support . Xserve G5 The Xserve is a discontinued series of rack-mounted servers that was manufactured by Apple Inc. between 2002 and 2011. It was Apple's first rack-mounted server, and could function as

3894-486: The same length. This is not necessarily true on 64-bit machines. Mixing data types in programming languages such as C and its descendants such as C++ and Objective-C may thus work on 32-bit implementations but not on 64-bit implementations. In many programming environments for C and C-derived languages on 64-bit machines, int variables are still 32 bits wide, but long integers and pointers are 64 bits wide. These are described as having an LP64 data model , which

3960-448: The size of data structures containing pointers, at the cost of a much smaller address space, a good choice for some embedded systems. For instruction sets such as x86 and ARM in which the 64-bit version of the instruction set has more registers than does the 32-bit version, it provides access to the additional registers without the space penalty. It is common in 64-bit RISC machines, explored in x86 as x32 ABI , and has recently been used in

4026-484: Was canceled. Slated for release in 2007, it was to be a uniprocessor-only northbridge. Its features were a 533 MHz DDR2 controller that supported up to 8 GB ECC memory, a 8x PCIe bus, integrated four-port Gigabit Ethernet with IPv4 TCP / UDP offloading, USB 2.0 ports, a Flash -interface. The northbridge contains an integrated PowerPC 405 core to provide system management and configuration capabilities. IBM uses its proprietary Elastic Interface (EI) bus in

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4092-1050: Was discontinued in 2011, and replaced with the Mac Pro Server and the Mac Mini Server . Before the Xserve, Apple's server line included the Apple Workgroup Server, Macintosh Server , and Apple Network Server . Apple introduced the Xserve on May 14, 2002 (released in June). Initially, two configuration options were available: a single-processor Xserve at US$ 2999, and a dual-processor Xserve at US$ 3999. Xserves sold before August 24, 2002 shipped with Mac OS X v10.1 "Puma" Server, while those sold after shipped with Mac OS X v10.2 "Jaguar" Server. On February 10, 2003, Apple released an improved and expanded Xserve lineup. Improvements included one or two 1.33 GHz PowerPC G4 processors, faster memory, and higher capacity Ultra ATA/133 hard disk drives. The front plate

4158-556: Was redesigned for a slot-loading optical drive. A new model, the Xserve Cluster node was announced at the same price as the single-processor Xserve, featuring two 1.33 GHz processors, no optical drive, a single hard drive bay , no video or Ethernet cards, and a 10-client version of "Jaguar" server. On April 2, 2003 the Xserve RAID was introduced, providing a much higher capacity and higher throughput disk subsystem for

4224-416: Was so far beyond the typical amounts (4 MiB) in installations, that this was considered to be enough headroom for addressing. 4.29 billion addresses were considered an appropriate size to work with for another important reason: 4.29 billion integers are enough to assign unique references to most entities in applications like databases . Some supercomputer architectures of the 1970s and 1980s, such as

4290-416: Was updated to ship standard with Mac OS X Server 10.6 Unlimited Client Server. In addition to improved functionality Mac OS X 10.6 Server added support for up to 96 GB of RAM. On November 5, 2010, Apple announced that it would not be developing a future version of Xserve. While accepting orders for the current model until January 31, 2011, and "honoring" all Xserve warranties and extended support programs,

4356-487: Was updated with Intel Xeon (' Harpertown ') processors, faster memory, and a maximum storage capacity of 3 TB when used with three 1 TB drives. The front-mounted FireWire 400 port featured in previous models was also replaced with a USB 2.0 port. The Xserve RAID was discontinued on February 19, 2008. On April 7, 2009 Xserve was updated to use Intel Xeon (' Gainestown ') processors, DDR3 memory, and NVIDIA graphics with Mini DisplayPort output. The update also saw an increase to

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