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My Own Little Cray
(Well, sort of)

About Cray	About the Cray 1
About the Sun 64 bit PCI based machine	About the NARC-1

About the Cray

    Back when I was a teen ager, and into my twenties, The Cray was the finest, fastest, most powerful, and most exotic computer in the world. These machines cost millions of dollars, and were, virtually, custom built, and installed. Adding to their mystique, were the uses to which they were put. There were Cray computers at the super secret NSA, advanced labs like Sandia, and Los Alamos, and places like the National Center for Atmospheric Research, NASA, and Caltech/JPL. The computers themselves were somewhat of a secret, and were little known, or known only by reputation. These computers were so secret, that upon their retirement, they generally had to be dismantled, and destroyed. These super secret, super powerful computers were not made in Silicon Valley, or even in Los Angeles, or New York. They were made in Chipewa Falls, Wisconsin. This added to the romance of these limited production machines. I.B.M. DEC, Data General, and other companies, would make large numbers of computers like the Ford or GM of the computer industry. In contrast, the small number of craftsmen at Cray would only make a limited run of high quality, specialized machines in their little shop in northern Wisconsin, in the manner of Rolls Royce. Unfortunately, it is rather difficult to get exact specs on the Crays, other than their performance in gigaflops. This is in part due to the custom nature of the machines, but is reminiscent of the Rolls Royce policy of not disclosing engine horsepower ratings for their cars.
       The legendary Semour Cray, was one of the pioneers of computer design, and the father of much of what we take for granted, in terms of performance. He left CDC, a company he had founded, to begin work on a new generation of high performance computers, in 1971. The term "Supercomputer" which was coined to designate Cray's new wonder designs, gives an indication of just how much he had advanced the state of the art. Once Cray Computers became successful, Seymour Cray left the company, and started Cray Research. He did this for the same reason that he left CDC after it became successful. In an interview, Cray explained that once a computer company becomes successful, it loses the ability to innovate, relying on evolving it's products so that it can retain it's customer base. A successful company just has too much to lose, to risk untested technology. It is a real tragedy that this man had his life cut short by a drunk driver. While a senseless death is always tragic, and certainly my sympathy goes to the Cray family and friends, the loss to the progress of the cutting edge of computer development can only be guessed at.
    Cray Computers has, for now, relinquished the title of producing the worlds fastest supercomputer. As of this writing, SGI,

and IBM are fighting over the title, which goes back and forth. Even so, Cray will forever be associated with the breed which it fostered, so many years ago. Even without the leadership of it's namesake, Cray computing remains at the forefront of this very rapidly moving leading edge. As of this writing, the Cray X1, is rated the 29th fastest, down from being the 20th fastest machine in the world. This is pretty respectable, particularly from such a relatively small company; but Cray will certainly be on top again, as the numbers slide back and forth, and new developments continue to be made. It is also interesting to note, that the Cray achieves this performance with 504 processors. The next computer up the list uses 2200 processors, and the two fastest computers, the Blue Genie uses 32768 processors, and the Columbia uses 10160 processors. This would seem to indicate that the basic design of the Cray CPU, and of it's processing architecture, have considerable potential for development.
The effect of the original Cray company, is still widely felt. Cray partnered with CDC, Sun, SGI, and the U.S. government. All of these companies benefited, and continue to benefit from the association. It trained numerous designers, and pushed the expectations of an entire industry. Nearly all of the major players in the supercomputing arena, had either been associated with the Cray company, as with SGI, or are using engineers, and techniques taken from the old Cray company.
The Cray Operating System (COS), and latter Unicos, are both variants of Unix. The native programing environment is C, though there is also FORTRAN available. Cray went out of business for a while (1995), but was eventually resurrected, and is now associated with Silicon Graphics. For years, it was rather reassuring to have Seymour Cray at the head of the computing world, rather like the Einstein or Edison of supercomputing. With his star dimmed, it is hard to say who or what will drive future developments.

The Early Cray machines

Unit	Clock	Ram	HD	Registers	Megaflops	vintage
Cray 1	12.5ns 80mhz	4mb (64x1mb)		64	80+	1976
Cray XMP	8.5ns (x4cpu) 118mhz	32mb (64x8mb)	2gb ssdisk	64	220	1985
Cray YMP	6ns (x8cpu) 166mhz	512mb (64x64mb)	2gb ssdisk	64	1000	1990
Cray 2	4.1ns (x4cpu)	1gb (64x128mb)		64		1990
Cray 3	2.08ns (x4cpu) 480mhz	1gb (128x512mb)	20gb	64		1992
Cray YMP8I	2.08ns (x8cpu) 480mhz	1gb (64x128mb)	2gb ssd 79gb drive	64		1993

About the Cray 1

As much of a lasting mark as they made on the future of the computer, and even on the culture at large, there were only a grand total of 85 Cray-1 super computers delivered. At a cost of between 5 and 8.8 million 1976 dollars, it's no wonder. This cost did not include the power supply unit, the hard disc (then called a fixed disc), or the computer, usually a CDC machine,

used to enter the data. Crays generally went into specially constructed rooms, with custom air conditioning units, and were themselves constructed, rather than manufactured in the traditional sense
As can be seen from the table above, incomplete though it may be, it is well within the capabilities (and budget) of the average enthusiast to put together a machine to roughly equal some of the earlier Crays. The main problem is with the CPU. Cray rates their processor speed in nanoseconds, rather than the more familiar Megahertz. It is easy enough to convert, and I have done so in the table, giving both numbers. It can be seen that current processors from AMD, and Intel easily match, and exceed the speeds of the early Crays, but there is more to processing power than clock speed. Crays used 64 bit processors, while the Intel/AMD units use 32 bit processors with 64 bit data paths. Some Cray processors have two math units. There are other architectural differences as well. There can thus be no direct comparison, at least not on the basis of speed alone. There is also the fact that, except for the Cray 1, Crays used more than one CPU. There are, in addition, some features that have never been implemented on standard PC's. One of these is the solid state disk, which can greatly speed up data intensive calculations.
The aesthetics of the Cray were as striking as the performance. These computers were designed for the ultimate in performance and efficiency. This was a case of form follows function, which actually enhanced the look and form of the machine. In contrast to the metal boxes of most of the day's computers (Most of today's computers as well), these machines were unique and individualistic. Everything was thought out, even to the extent that the computer had a radial shape to minimize the lengths of wire runs. The wire runs themselves were all of the same length. There was also special attention paid to cooling, which seemed to be part of Seymour Cray's special genius. The Crays were crafted as much as they were engineered. The Cray 1 weighed 5-1/2 tons, arrived in two refrigerated electronic vans, and needed more than 30 construction workers, engineers, and helpers to move it into the computer room. In 1978, the first standard software package consisting of the Cray Operating System (COS), the first automatically vectorizing Fortran compiler (CFT), and the Cray Assembler Language (CAL) were introduced.

CRAY-1 Supercomputer
	CPU 1 or 2 64Bit 80mhz, vector
	RAM 4mb to 16mb (64bits x 1mb to 4mb)
	Capacity 80 to 133 mfps

About 64 bit computing, and the Sun PCI machines

One thing which is a given, about any sort of attempt at emulating a Cray, is that this will have to be a 64 bit machine. For several years, the only option for the home user was a purchase of a Sun Sparc machine; but this is no longer true. There are presently four 64 bit players in the work station, PC arena. They are the Sun Sparc, the AMD Opteron, the Apple G5, and the Intel Itanium. Of the four, the Sparc is by far the oldest, having been around for ten years or so. More recently, Intel has announced a new Pentium 4 CPU, with 64 bit capacity. Still, all of these systems cost a fortune, except one. The Sparc machines are quite expensive new, but unlike the rest of the crop of 64 bit machines, it is possible to buy a used Sparc machine, at a reasonable price.
In the late nineties, Sun introduced it's Ultra series of PCI based Sparc machines, in an attempt to lower it's prices, and to make it's platform a bit more accessible. Previous version of Sun Sparc machines had used Sun's own Sbus system for expansion, and had used a variety of proprietary memory modules. This tended to narrow the expansion options, and raise the prices of these high performance machines. Previous Sparc machines had also used a proprietary connector for the video monitor, known as the 13W3-M, as opposed to the standard VGA style HD15-F connector. The Ultra series of Sparc machines use a PCI architecture, and some models

can use standard PC style monitors, and even standard PC style 168 pin ram. The first generation of these machines can now be had for between $100, and $300, or perhaps a bit more depending upon how they are configured. The Ultra 5 and 10 machines even take standard IDE drives. The Ultra 60 is able to support 2 processors. The Ultra series were replaced by the Blade series.
    Like the early Cray machines, the Sun Ultra machines came in a variety of configurations, with varying amounts of memory, processor speed, and processor number. Also like the Cray machines, these use the Unix operating system. What is most relevant to this discussion is the fact that, like the classic Cray, the Sun Ultra machines use 64 bit processors.
    If you are looking for a Sparc of your own, and want to test the waters of 64 bit RISC based computing, without spending a fortune, you may want to consider a Sun Ultra 10. These are probably the most desirable of the Ultras for a couple of reasons. The Ultra 10 is housed in a tower case, with 4 PCI slots, will take up to 1gb of 168 pin 50ns or 60ns JEDEC DIMMs, ECC RAM, and uses a standard IDE drive, as well as a VGA monitor. It runs at a CPU speed of up to 440mhz, which is not very impressive these days, until you realize that this is 64bit RISC computing.
    The smaller, desktop case Ultra 5 is probably the least desirable of these machines, though it is also the least expensive. It is only capable of taking 512mb of ram, and only has 2 fully usable PCI slots. It also only has room for a single IDE drive, unless you remove the floppy. The Ultra 30 machine shares many of the virtues of the Ultra 10, and adds the capability of taking 2gb or RAM. Unfortunately, this is 200 pin RAM. This machine also requires the use of SCSI drives, though it does use a VGA monitor, and has 4 PCI slots. The Ultra 60 is similar to the Ultra 30, but is available with dual processors.
    Though there are many ways to categorize computers, and the processors which run them, one of the more common methods is to separate them into RISC, and CISC. RISC (Reduced Instruction Set Computing), and CISC (Complex Instruction Set Computing) The Cray machiens had RISC architecture, making them appear far less powerful than they were. According to Varmint Al, who ahd worked at the Lawrence Livermore laboratories, and who actually used Cray machines back in the 70s/80s, a 400mhz Celeron, with 256 mb or ram was about a quarter of a Cray-1, running at 80mhz, with 4mb of ram. The 64 bit architecture, as well as the RISC configuration is the reason. Thus, I would stack up my "old" Ultra 10 machine, running at 440mhz, and using a gb of ram, against any Pentium 3, or Pentium 4 machine out there.

All numbers shown are maximums

Model	Case	CPU	RAM	HD	Video	Drives	Expansion	Network	Date
Ultra 5	Desk top	IIi 270- 400mhz	4x168pin 512mb	1xIDE 4.3 to 20	8 or 24 bit	CDRom 3.5"	2.5 PCI	10/100	01/01
Ultra 10	Tower	IIi 300- 440mhz	4x168 1gb	2xIDE 4.3 to 20	24 bit + UPA	CDRom 3.5"	4 PCI	10/100	01/01
Ultra 30	Tower	II 300- 440mhz	16x200 2gb	2xSCSI 4.3 to 36	2xUPA	CDRom 3.5"	4 PCI	10/100	02/99
Ultra 60	Tower	II 2x300- 450mhz	16x200 2gb	2xSCSI 4.3 to 36	2xUPA	CDRom 3.5"	4 PCI	10/100	07/02
Blade 100	Desktop	IIi 500mhz	4x168 2gb	2xIDE 15 to 20		CDRom 3.5" card	3 PCI	10/100

Ultra Sparc IIi
SPARC V9 compliant 64-Bit
4-way superscalar
VIS Instruction Set
Clock Frequency : 550, 650 MHz
L1 Cache :
16 KB Primary direct-mapped data cache
16 KB Primary instruction cache (2-way set associative)
L2 Cache : 512 KB (4-way associative), Integrated on-chip
Max Memory : 16 MB - 4 GB
Memory Type : PC 100/133 MHz SDRAM memory interface.
Bus Interface :
Integrated Rev. 2.1 PCI Compatible interface
33/66 MHz, 32-bit, 3.3 V
Four-way superscalar pipeline, 64-bit wide memory interface with 800 Mbyte/sec capacity combined with 64-bit wide internal buses.

UltraSparc IIe
Instruction Set : VIS Instruction Set
64-bit SPARC V9
Process Technology :
CMOS 0.18 micron process
6 layer AL metal
Clock Frequency : 500 MHz
L1 Cache :
16 KB Primary direct-mapped data cache
16 KB Primary instruction cache (2-way set associative)
L2 Cache :
Unified instruction and data cache
512 KB (4-way associative)
Memory Type : 83 MHz SDRAM with ECC
Bus Interface : Integrated Rev. 2.1 PCI Compatible interface
Four-way superscalar pipeline, 64-bit wide memory interface with 800 Mbyte/sec capacity combined with 64-bit wide internal buses.

So all right, maybe these machines can perform like the early model Crays, but they look nothing like the Cray, and the OS, though another variant of Unix, says Solaris. Well, I am addressing these issues in my newest old computer, which is detailed below.
Presently, Sun is up to the Sparc 4 cpu, which has significant speed and architecture improvements over the II series. Sun is also supporting the AMD Opteron 32/64 bit cpu. Unfortunately, both of these are a bit expensive these days, though as always the price will eventually go down. The Opteron solution will run either Linux (Sun recommends the Susse distribution), or the x86 version of Solaris. It will also run Windows, though there is little point.

About the NARC-1

    There is little hope for the non-millionare to produce a computer which will rival the contemporary Cray, but it is possible to set up a machine which can mimic the old Cray-1, and Cray-XMP/YMP machines. I have gleaned some information on the specs of the machines, and have entered it in the table above. The problem with setting up a table like this for a custom machine, is that the specs do not cover the whole series produced. In particular, it is difficult to get exact data on the mass storage systems used. Often, these storage systems were not even built by Cray, but were ordered from other sources by the purchaser. Cray machines use a variant of Unix, and will often use resources located on other machines. This is particularly true of hard drives, and other mass storage systems. In many cases, other computer systems would function as file servers. The Cray would load needed data into it's silicon disk (ssdisk), as needed, and use this as a virtual hard drive. the table is primarily based on information from NCAR, which has been using Crays from the earliest models, and continues to use them today.
    I am presently using a Sun Ultra as a sort of a Cray emulator, and am considering putting it in a home built cabinet fashioned after that of the original Cray-1. The NARC, if ever built, will probably be an Opteron machine, using one of the higher end multi processor boards available. Some of these boards can hold up to 32gb of ram, and have significantly high bus speeds. The Apple G5, is compared to the Opteron here. The two processors are the leading lights in 64 bit processing. The SPARC, and Intel 64 bit offerings are way too expensive for most users. The Intel unit is probably inferior to the newest offering of the Opteron.
    Below is my present fantasy Cray emulator. I plan on using a 64 bit CPU, either the Opteron, or perhaps a motherboard out of a Sun Ultra machine. The operating system will be Solaris 10; but there will be a difference. Sun has recently made Solaris open source. What this means is that I will have access to the code, and be able to make some modifications, if I wish. I am hardly an expert programmer, so the changes I make will be small. In the main, they will center on making the Solaris operating system appear to be the Cray operating system. This will be accomplished by changing the appearance of prompts, and splash screens. I understand that this is all rather silly, but there is no accounting for the power of an obsession. I even plan on construction a case, of wood, plastic, or metal, resembling a small scale Cray-1. The modified drawing of the dimensioned case is shown below. So, will I ever do this? Probably not; but I can dream.

NARC-1 (Not A Real Cray)
	CPU Opteron (x2) or Sparc (x2)
	RAM 32gb
	Storage SATA
	Operating System Solaris 10, modified