Workstations for CAD/CAM/CAE

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State committee of Russian Federation on higher education

The Moscow State Technical University by him(it). AD. Áŕóěŕíŕ

Faculty ĐĘ9

The abstract

Workstations for
CAD/CAM/CAE

The schedule

I. Introduction

II. Aspects of choice of a workstation

III. The browse of the market of workstations

I. Introduction

Them any more do not do(make) by such, as earlier!

Henry Ôîđä

To workstations in CAD/CAM/CAE - systems the high requirements in productivity, stability of operation, compatibility and universality are showed. The choice of a workstation is the uneasy task. A basis is the orientation to one of two main platforms is UNIX and Windows NT. The requirements to productivity are pawned by the software.

The high-efficiency workstations, which have appeared in the domestic market, strongly and confidently win popularity among the users. They easily consult(cope) with any complex(difficult) tasks, for which execution still computers Silicon Graphics recently were necessary. Therefore organization, which has decided(solved) to enclose some tens thousand dollars on acquisition of workstations, collides occasionally with a number of very difficult questions: what model to select, on what platform to be oriented, what should be the configuration?

To clear up solution these and some more many other problems connected to acquisition of this expensive engineering, we shall consider the points of view of representatives known foreign and domestic-owned firms.

Aspects of choice of a workstation

1. Technical aspects of choice

First, the engineering should be reliable. Secondly, manufacturer íîé. From a beginning 70 years, when the first program complexes have appeared, and down to recent time of CAD/CAM-system were oriented extremely to acceleration of the process of creation of the drawings, used only two-dimensional graphics, and a key factor at a rating of their efficiency was the productivity of the central processing unit (ÖĎÓ).

With increase of the requirements to CAD/CAM-systems the special attention began to be given not so much to productivity ÖĎÓ, how many collection of metrics mirroring fitness of the computer for execution of this or that task.

Now it is not so enough of only one powerful central processing unit. Undoubtedly, the given requirement still is one of defining, however there are many certificates, when also superfast central processing unit be unable in a singleton to decide(solve) all spectrum of the set tasks.

To define(determine) required technical parameters, briefly we shall analyze three main operations, which are made by(with) the computer by operation with the majority of CAD/CAM-systems.

1. Loading of a kernel and units of the system

Practically all existing CAD/CAM-systems represent structures of units, each of which responds for implementation of this or that function. The tendencies of development of CAD/CAM-systems consist in constant increase of quantity(amount) of units and in more and more narrow îđčĺíňčđîâŕííîńňč of each unit on execution of the strictly defined operations. Such specialization results that the user will involve in each new version in unit of time increasing quantity(amount) of components of CAD/CAM-system.

At similar mode of operations the intensive data exchange between the hard disk, RAM and central processing unit is carried out. The speed of operation of the user thus directly depends on bandwidth of the bus linking these devices.

2. Recalculation of geometrical changes of model

If to abstract from productivity ÖĎÓ, the time required for the given operation, in main depends on a size of model, and the recalculation of changes occurs, as a rule, on all model, and not just in the updated part. Thus model, which size, as a rule, exceeds a size of the cache memory which is taking place on the central processing unit, “çŕęŕ÷čâŕĺňń˙” in the RAM and is gradually enumerated by the processor.

And, as well as in the first case, the speed of operation of the user depends on bandwidth of the bus.

3. Visualization of model

Those times have passed, when the designers were content with two-dimensional or three-dimensional wire performance of model. Now unconditional requirement of the users is the performance of model in natural sort and possibility to manipulate her(it) in real-time mode.

The graphics computer power depends only from ýô ôĺęňčâíîńňč of specialized accelerators and … on bandwidth of the bus linking the RAM and the accelerator.

2. Price aspects of choice

Usually first of all user pays attention to the price. There is a popular belief, that at high cost of the software the engineering should be as it is possible more cheaply. Such approach though is correct, but nevertheless requires some correction.

It is well-known, that too much powerful computers does not happen. Necessarily there will be a possibility something to speed up and to improve. If earlier plane drawing sufficed to the designer, now it(he) wants to work with three-dimensional model. And it is not simple with three-dimensional model, and with the “filled” three-dimensional model. And it is not simple with the “filled” three-dimensional model, and it is necessary with the solid-state “filled” three-dimensional model. Differently, the tasks always anticipate possibilities of engineering.

We shall be frank — computers become cheaper extremely slowly, however thus their possibilities very fast grow, that carries on to increase of productivity of work of the users, rise of quality of operations both lowering of periods of manufacture and cost of a product.

Thus, we come to concept of specific cost, when at the saved or slowly falling price efficiency of usage of the computer system sharply grows.

3. Common aspects of choice

Having considered technical and price aspects, we shall proceed(pass), at last, to common, which, despite of apparent insignificance, play in operation the large role.

Most frequently mentioned — a simplicity in circulation. Frequently it is necessary to hear about complexity of usage of CAD/CAM-systems in comparison with personal computers. Really, hardly having begun to operation, you collide with the unusual terms such as root, boot, shell, domain etc., without which understanding of effective operation will fail. When it is necessary to save the information on the external carrier, to be connected in the external network or to change the configuration of the computer, it is necessary to call ńčńňĺěůčęŕ. And it(he) one on twenty men scattered on territory in five square kilometers. In the total the routine operation takes away some hours. And as it would be good — ňęíóë in “icon” and has received desirable result!

The following aspect we shall name ďđčńďîńîáëĺííîńňü to life. Whether there is a sense to hold on desktop two computers, one of which is intended for operation with CAD/CAM-systems, and another — for printing the reports, compilation of the tables, operation with email čň.ä.? Why it is impossible to avoid empty expenditure of money and to combine one with another?

One more important aspect — the human person. Who has told, what music prevents you to work? Or what the resources for creation of effective presentations are not necessary to you? All this is necessary for creation on a workstation of creative conditions to prepare a video and ŕóäčîčíôîđěŕöčţ and convincingly to present to its(her) chief. And eventually to achieve that you wanted.

It is possible to result many more parameters, to which there should correspond(meet) computer CAD/CAM/CAE-system, however we shall be limited only to one. Let's name it(him) — skill to communicate. How many time, working above the twenty seventh version, you received from a department of account of durability results on fourteenth? Why to not discuss a construction of a product, having arranged news with all involved in operation above the project by the colleagues? Or, at the worst, to discuss all on the phone, having the same detail on the screen? Why to not supplement model of a video, by the voice and text information and to not send to the colleagues, that they, having pressed the button, have seen, have heard and have read everything, what you want by him(it) to transfer?

III.Îáçîđ Market of workstations

1. Silicon Graphics/CRAY

In conditions of the fast varying market of computer CAD/CAM-systems will survive only the one who can most full mirror in production the modern requirements. The corporation Silicon Graphics/CRAY is known for that concentrates all forces on achievement is set íîé of the purpose, offering production, under many characteristics exceeding production of the competitors. So it started in the field of graphics supercomputers for the industry of entertainments, so it proceeds and in sector CAD/CAM.

1. Personal workstations Î2

The workstation Î2 is constructed on the basis of the new unified architecture of memory UMA (Unified Memory Architecture) — of the inheritance CRAY Research. In its(her) basis lays superhigh-speed system of exchange, on
With which “hang” and to which have equal access all devices of the computer — the processor, memory, disks, graphics čň.ä. The speed of exchange is equal “system” 2,1 Gbyte / with. The term “bus” here is not mentioned deliberately. And in what a difference. “Bus” is possible is to compared with îäíîęîëĺéęîé, while by(with) the system in Î2 — it faster ěíîăîďîëîńíîĺ a double-sided highway.

Earlier we have placed(installed), that deceleration in operation of CAD/CAM-system
Occurs not on fault ÖĎÓ, and in main because of slow operation of the bus — by that îäíîďîëîńíîé of a road, on which the information from the processor to the accelerator will not act(arrive) until there will pass the information from the processor to hard disks. In Î2 it does not occur.

32-bit graphics with double-buffer, “native” graphics subsystem OpenGL and hardware support of mapping of texture and Z-buffer which has been built - in in a workstation Î2, provide the users with high efficiency and quality by operation with 3Dčíôîđěŕöčĺé. Î2 has the specialized mechanism of image processing, which is accelerated such operations, as, for example by(with) convolution. The equipment for mapping texture also makes possible panning, zooming and rotation large, images, distinguished by a high-resolution, in real time.

In addition to Î2 the user also receives the emulator Windows 95 or Windows NT with all components, fixed them, resource for operation with Internet Netscape Browser, per century of development ěóëüňčěĺäčéíűő of the applications you receive not only usual email, but also and IRIS Annotator — ěóëüňčěĺäčéíóţ mail, ShowCase — a resource for creation of presentations, complete tooling for operation with a sound, colour and video.

Base package in addition to set forth above includes 32 Mbytes of the RAM, hard disk on 1 Gbytes, 4X CDROM, 17äţéěîâűé the screen monitor and, ĺńňĺńňâĺí but, keyboard and mouse.

2. Professional workstations ÎCTANE

Workstation ÎCTANE — one of the most modern high-efficiency systems combining in power of symmetric multiprocessing (SMP) — one or two processors MIPS R1000 — and the desktop graphics system to the architecture on the basis of internal commutation (crossbar switch), permitting to various computer subsystems to cooperate directly with each other, not creating interferences and not competing with other subsystems.

In a workstation ÎCTANE the graphics possibilities are realized which provide realness of the maps and high efficiency by operation with polygons. The system is distinguished by(with) a high degree of modularity and scalability. The user can select one of three graphics configurations depending on his(its) current and future tasks. For the applications requiring(demanding) additional working space or two independent screens, ÎCTANE gives variant dual-head.

Offering ÎCTANE, the company Silicon Graphics develops(unwraps) symmetric multiprocessor development on the basis of the desktop server. In ÎCTANE there is a possibility of support of simultaneous and independent operation of one or two processors MIPS R10 000 at processing the several not intersected tasks. The multithread 64-bit operating system of a workstation ÎCTANE in a combination to the multithread applications even more raises computing power of the system.

ÎCTANE has modular extended structure supporting a wide range of peripheral units and devices of input / output. The kernel system includes standard built - in Ethernet 10/100 Ěáčň/with and two buses Ultra SCSI. Besides ÎCTANE supports three additional slots PCI-64, that allows to connect the various modern peripheral equipment. For the extension of possibilities of a workstation for frameworks of devices with support PCI ÎCTANE is equipped with four high-speed slots XIO with a transfer rate 1,6 Gbytes / c (in the settled mode).

2. KLONDIKE

The productivity of workstations on the basis of the processor X086 for last year has grown more than in 2 times. At the expense of perfecting the technology the high bound of frequencies has reached(achieved) 300 ĚĂö.

The steady lowering of the prices on a background of growth of productivity provides high competitiveness of the platform Ő086 and perspective on the future. Due to this the computers on the basis of processors Intel successfully compete to more expensive(dear) RISŃ-systems.

Let's consider features of operation with a graphics. Irrespective of a type of the platform (SUN, SGI, Apple or PC) such operation requires(demands) execution of the large size of calculations and transmission of huge data arrays. Thus it is necessary to take into account, that practically in all cases the quality of the map directly depends on size of the processed data. For example, by operation with the raster map than higher is the permission of a picture, especially fine details on it(her) can be displayed and that the greater size she(it) borrows(occupies) in memory. In a case if we work with the two-dimensional vector map, it is understandable, that than a lot of vectors makes the map, especially realistically and precisely it will look. For a 3D-graphics are important both first and second conditions, as only at their observance it is possible to achieve maximum verisimilitude of mapping of 3D-objects. That the system successfully handled graphic datas, the observance of a condition of balance of each subsystem is necessary.


Figure 1

Let's consider three variants of the system (fig. 1). Each of variants represents some sequentially connected pipes of the different diameter forming one common pipe with defined bandwidth. The system 1 has maximum productivity and, naturally, maximum cost. The systems 2 and 3 have different productivity, but identical cost. It is clear, that at fixed cost the system 3 has maximum common productivity. Therefore at the expense of balance of the configuration under the defined circle of the tasks it is possible not only to save a significant part of resources, but also to raise(increase) productivity of the system as a whole.

On our sight, it is meaningful to divide graphics servers into three main directions according to the soluble tasks: both CAD-graphics; a raster and 2D-vector graphics; processing of the videomaps. I list main features of system operation on it to three directions:

1. CAD- And the 3D-graphics shows the additional requirements to a videosubsystem, requires(demands) presence 3D of the accelerator for fast visualization of complex(difficult) three-dimensional objects, and also powerful processor subsystem for the fast miscalculation of a vector graphics and special effects.
2. The raster and 2D-vector graphics requires(demands) the powerful 2D-accelerator with support of high-resolutions and improved colour rendition, large size of the RAM of the system, powerful processor subsystem for the fast miscalculation of conversions of the map;
3. The processing of the videomaps requires(demands) a disk subsystem with a high speed of exchange and possibility of recording of the continuous dataflow, specialized input\output system of the videomap, powerful processor subsystem for fast arranging of the map and nonlinear videoediting.

If to generalize told, for any graphics server the correct choice is important:

1. The processor,
2. Disk subsystem,
3. Subsystems of memory,
4. Graphics subsystem.

Now it would be desirable to touch questions of concrete implementation of each of subsystems.

It is understandable, that the powerful processor is necessary for any graphics server, therefore as a processor subsystem we offer two variants on the basis of the most powerful processors: Intel Pentium II and Pentium Pro. The systems on the basis of processors Pentium Pro differ ěíîăîďđîöĺńńîđíîńňüţ, traditional compatibility and a little for today by the greater productivity. Systems on base Pentium II — it not only technology MMX, higher clock rate, AGP-bus, but also significant ďĺđńďĺęňčâíîńňü and äčíŕěč÷íîńňü of development.


The diagram 1

The significant share of common productivity of the graphics server is made by(with) productivity of a disk subsystem. Disk subsystem is meant as the complex consisting of the controller of the hard disk, interface and hard disk. The advantages of the SCSI-interface are well-known: flexibility, universality, ęŕńęŕäčđóĺěîńňü, large length of the bus and noise stability, high speed of data transfer. However it(he) needs to be applied extremely when it(he) is really necessary and can bring real advantage(benefit).


The diagram 2

Let's try to estimate, as far as the application in the graphics server of a disk subsystem with the IDE-interface is favourable. Let's select the most typical disk drives of the carrying on manufacturers of hard disks for interfaces SCSI and IDE and is comparable their productivity under the test ZD High End Disk WinMark97 (diagram 1). From the given diagram it is visible, that some high-speed disk drives IDE do not concede on productivity to disk drives SCSI. If now to pay attention to the price for 1 Mbytes of disk memory for the same disk drives (diagram 2), it is visible, that cost of 1 Mbyte on IDE-disk drives in 3-4 times is lower, than on SCSI-disk drives. The third diagram visually shows, that the efficiency of nesting of money, from the point of view of productivity, on a unit of value of 1 Mbyte for IDE-âčí÷ĺńňĺ đîâ in 2-2,5 times is higher, than for SCSI. In the given calculations and diagrams with the purpose of simplification cost SCSI- and IDE-controllers is not taken into account(discounted); The registration of their cost will result even in some growth of voices for the benefit of a IDE-disk drive. The disk subsystem on the basis of disk drives with the IDE-interface has the right to existence in some models of graphics servers — important only correctly to select the type of a disk drive.


The diagram 3

It would be desirable to pay attention to choice of a subsystem of memory as 10Ěáŕéň/with. Even if you buy the very dear(expensive) Raid-array on hard disks Ultra Wide SCSI, you do not receive speed of exchange above than 40 Mbytes per second (if not to take into account possibilities of the interface Fiber Channel). Let's analyze the diagram given in a fig. 2. On an axis Y the speed of exchange with memory, on an axis X — a size of the current working storage is shown. In the system shown on the given diagram, 64 Mbytes of the actual storage are placed(installed), other memory is selected(allocated) as virtual. Some part of memory borrow(occupy) an operating system and application handling the data (in our case — about 40 Mbytes); the further loading of the data by size more than 24 Mbytes carries on to derivation on the hard disk of the virtual storage filling in shortage of the actual storage. The call to the block given, taking place in the virtual storage, is decelerated up to 10 Mbytes per second, that is almost in 50 times. If shortage of memory essential (1,5-2 and more time), the system practically continuously starts to work with the hard disk and average speed of operation with memory makes hardly more than 10 Mbytes per second. Thus, if you save on the RAM at the expense of other subsystems, you decelerate operation of your system more than in 50 times. Differently, operation, which should be fulfilled for 6 seconds, for you 5-7 minutes will be fulfilled; in this case it is not so important, to what you have processor or videoadapter, as far as the RAM in the computer is fast. All âűřĺńęŕçŕííîĺ is especially important for graphics servers, where on definition there is an operation to huge data arrays. Therefore, on our sight, at choice of memory size it is necessary to be guided by the simplified formula of sort: ÎĎ = 32Ěáŕéň (operating system) + 2 maximum sizes of the processed file without compression.


Figure 2

The common guideline is those: if during operation the indicator of call to the hard disk seldom dies away or shines continuously, you should increase size of the RAM.

The corporation KLONDIKE offers powerful graphics servers designed with the registration higher by one of the fastest and most central subsystems of the computer. At choice such as and memory size the number of standard errors is usually made. In modern operating systems the shortage of the actual storage for the task can be eliminated by means of the so-called virtual storage, which is selected(allocated) on the drive automatically and is limited only to presence of free space on it(him). Let's look, that occurs in this case. The speed of exchange with real memory of the processor makes approximately 500 Mbytes per second (66 ĚĂö˝8 byte for clock tick (in an ideal case) = 528 Mbytes), and the speed of exchange with the hard disk is defined(determined) in main speed of head positioning of reading / recording, bit density on a surface, by speed of rotation of a slice and makes about the listed requirements and optimized on three main directions: CAD- and 3D-graphics; Raster and 2D-vector graphics; processing of the videomaps. In each class of computers the systems represented on the basis of processors Pentium II and Pentium Pro. Most strength of solutions, offered us, is, on our sight, the balance of all subsystems of workstations, offered us, and optimal relation “price / productivity” for them. In systems for processing raster and 2D-graphics the special attention is given to a colour rendition and processing of the large datafiles; in workstations for CAD- and 3D-graphics are applied PCI- or AGP-accelerators with the hardware acceleration and support OpenGL- and Direct of 3D-interfaces; the computers intended for processing of a video and nonlinear videoediting, have not only fast disk subsystem, but also modern resources of input-output of the map.

3. Classics

Correctly to select model of a workstation, first of all it is necessary to define(determine), she(it) intends for operation in which data domain. If it is the usual business - applications, special requirements (except for minimum to speed, capacity of the hard disk and RAM) is not showed. If it is areas ŔŃÓĎ, CAD or multimedia, there are hard requirements to computational capability and characteristics of the videosystem of a workstation. Usually workstations for these data domains name as graphics workstations.

Traditionally as leaders among the manufacturers of workstations are considered Sun, SGI and DEC. The workstations of these manufacturers — are computers on RISC-processors using various dialects of an operating system UNIX. Naturally, their application is limited to that software, which exists for the given platforms. Besides the price of graphics workstations always was very high.

As alternate variant of a workstation now with small íŕň˙ćęîé it is possible to consider(examine) the PC with one or several processors Pentium Pro or Pentium II and powerful videoadapters. Such servers lag behind in a little computational capability and not always provide sufficient productivity for solution of the graphics tasks, however have huge advantage among the applications, as use operating systems Windows 95 and Windows NT. Besides they are distinguished not simply considerably by(with) lower price, but also best relation “cost / productivity”.

There is enough for a long time of workstations on RISC-processors the corporation Digital makes also. They are based on fastest in the world processors Alpha (processors with clock rate 700 ĚĂö) recently have appeared. Until recently Alpha-servers got in the same category, that Sun and SGI, but recently situation has varied. The prices for Alpha-processors and system boards for them considerably have fallen. It has taken place in many respects that the known companies Samsung and Mitsubishi were connected to production which have concluded the license agreements with Digital. Were created the new processor 21164PC, working on frequencies 300-600ĚĂö, using additional instruction set for multimedia, and new ęîíńňđóęňčâ of the system board. The workstations will gather now in tanks ŔŇŐ with usual ĐŃI-slots of the extension, that will allow to use for Alpha-servers standard peripheral units. The frequency of operation of the system bus already now reaches(achieves) 333 ĚĂö. It is essential to reduce the price of Alpha-servers the organization of their production with Russia will help. Such project is in a stage of implementation for the “Classics” corporation and its(her) partners.

The Alpha-servers under handle Windows NT function, that considerably facilitates their maintenance. For Windows NT Alpha there are more 1800 “native” applications; besides due to the technology FX! 32 the applications Win16 and Win32 for ő86 and even the applications for DOS are supported. And the applications ő86 are fulfilled not in the mode of emulation, as in systems Sun and SGI, and are assembled in Alpha-codes, that allows to provide more high speed of operation.

Usage of a chip 21164PC enables to fulfil the 3D-applications approximately in 3 times faster, than in systems basing SPARC-processors Sun. Alpha-processors have sufficient power and for fast execution of the mixed video-multimedia of the applications.

As was already marked, the new Alpha-servers should borrow(occupy) a part of sector of the market, which while is fixed behind workstations Sun and SGI. It, on our sight, is quite real due to the listed above arguments. Most important of them are, first, price, more precisely integral characteristic — “ the price / (productivity + reliability), and, secondly, possibility of usage of an operating system Windows NT. The reliability is guaranteed by application only of hardware recommended the experts Digital, and all-round ďđĺäďđîäŕćíűě by testing of workstations.

The Alpha-servers of the Russian production will considerably (on 30-40 of %) more cheaply similar products Digital and under the price will be comparable to the PC Intel. The experts of “Classics” for a long time work with engineering Digital and in a status to provide qualitative technical and service on all operation phases. Though the graphics servers are intended for solution of enough complex(difficult) tasks, organizations having need(requirement) for such engineering, is not only in Moscow and St. Petersburg, but also in other cities, where the representations of “Classics”, for example in Krasnoyarsk, Tashkent, Voronezh operate. So perspectives for Alpha-servers of the Russian assembly promising.

4. IBM

   1. Common aspects of choice

   Very much frequently it is possible, that advantages and the lacks of workstations try to estimate separately from the tasks, which should be decided(solved) with their help. However in practice the real productivity in many respects depends on the concrete application, for which this workstation is gained. It is not enough of standard samplings (SPEC etc.) for of ratings of serviceability.

   Business in that the standard parameters at all do not take into account such important nuances, as, for example, optimization of the application for operation with the defined operating system or computer architecture. In result can appear, that by operation even with the most advanced processor, which manufacturer does not give attention operation on such optimization, CAD/CAM/CAE-system will show the worse results, than on less powerful model with an operating system, under which the optimization was carried out(spent).

   Other important aspect of choice is the universality of the hardware platform in relation to other software packages which are not concerning base CAD/CAM/CAE-system: for example, system nonlinear ďđî÷íîńňíîăî of simulation, news, multimedia, and also ability of the given system to represent itself as a basis for repository. Really, it is much more favourable to contain staff(state) of the employees prepared for support of one hardware platform, than to have similar groups of the engineers on each sort of used systems.

   The special attention is necessary for giving and presence for the manufacturer of hardware of courses in Russian on training the system, technical and service experts of the customer.

   From others less significant on the first sight of aspects of choice would be desirable were to marked such, as by(with) certification according to the Russian standards, stability to faults of power supply, data protection and ergonomic metrics.

   2. Price aspects of choice

   In the computer world it is accepted to estimate cost of possession of engineering on a relation “price / productivity”. For workstations there are as a minimum such two metrics: for the processor and for a graphics subsystem.

   Very much frequently absolute price erraticly take as the main parameter at choice, notwithstanding what the computer system can result in loss of a lot of time and resources while in service “more cheaply”. On the other hand, it at all does not mean, that the price defines(determines) productivity. For this reason the relation “price / productivity” is the most correct metric of “value” of the computer system.

   It is necessary also to take into consideration, that frequently cost of the applied software can in two - three times exceed cost of hardware, therefore at purchase of the cheap computer money spent for the application, can appear unjustified.

   And nevertheless what to do(make), if the customer be unable at once to pay the computer system in that configuration, which most full meets the requirements the application? An output(exit) can be purchase of the certainly “facilitated” configuration, which, however, is capable to support operation of CAD/CAM/CAE-system at an initial stage of the project (training, implantation). To the moment of an output(exit) on a stage of industrial mode of operations the customer can íŕđŕńňčňü the RAM, add hard disks or, at last, replace the processor with one more powerful. In this case it is necessary to be convinced that the manufacturer of hardware can make upgrade enough “without serious consequences” and cheaply. It is necessary also to know about presence and cost of service support on the part of the manufacturer.

   3. Technical aspects of choice

   For the users working with systems CAD/CAM, the reliance is extremely important that the results of the done operation will not disappear because of any of annoying misunderstanding (such, as a breakaway of a network cable or power fail). Therefore it is necessary, that the hardware was highly reliable, the operating system provided protection of data integrity even at not regular completion of write operation on the local or remote disk. The operating system AIX favourably differs from other operating systems such as UNIX by high reliability of safety of the file systems, given at the expense of usage, JFS (Journal File Systems). JFS provides protection of data integrity by support of a magazine of all changes occurring to a file system. The magazine provides possibility of “rollback” (restoring of the previous status) at failure and essentially reduces common time of restoring of a working status of the system in comparison with traditional methods (such, as, for example, fsck). Important also that the file system JFS is “native” for operating system AIX, therefore its(her) usage is completely transparent for the user and does not require(demand) acquisition and číńňŕëëčđîâŕíč˙ of the additional package of the system software.

   CAD/CAM/CAE-systems are enough đĺńóđńîĺěęčěč and especially requiring to operation with memory. Therefore on some UNIX-systems with the traditional approach to construction of a kernel of an operating system the preliminary adjustment of a kernel on the defined parameters set by the class of the application (size of divided memory, valid quantity(amount) of the semaphores, maximum value of size of a data segment etc.) is required. As a rule, these parameters âçŕčěîçŕâčńčěű, and the adjustment of the system requires(demands) deep knowledge of an operating system and circuit(scheme) of its(her) interaction with the application, and consequently, higher qualification of staff. At this ambassador of change of parameters the repeated regeneration of a kernel and mandatory reboot of the system is required. For the users of operating system AIX, for example, the similar problems do not exist, as AIX has a dynamic kernel capable automatically to adapt to the requirements of the application during operation.

   The flexibility and simplicity of the configuration of the system as a whole is provided also with usage of the manager of logical volumes (LVM), which allows to unite physical disks in uniform space of disk memory and to arrange resources as required during operation. Really, in traditional UNIX-systems each connected disk should be formatted before inclusion it(him) in operation, therefore resource allocation is made at the moment of installation. But beforehand to define(determine) sizes of space for ńâîďďčíăŕ it happens difficultly: the requirements to it(him) can increase in process of complicating models, with which CAD-system works. Using LVM, the user AIX can not only “ on summer ” to add or to expand any area of an accessible disk space (including area ńâîďďčíăŕ), but also to reallocate allocation on the disk, to remove fragmentation, to create a mirror copy of the most important data.

   4. Computer systems IBM RS/6000 for CAD/CAM/CAE

   The carrying on designers, engineers, scientists and programmers for a long time know the set of workstations IBM RS/6000 as a powerful and reliable resource for solution of the modern tasks in the field of computer-aided design and complex(difficult) technical accounts. A combination high-efficiency hardware and the software with a complete set of the applications has made the set RS/6000 most fast developing in the environment of UNIX-computers.

   The set RS/6000 combines in itself processor technologies of a world(global) level with high graphics productivity working under the control of an operating system AIX, extended version UNIX.

   The workstations RS/6000 are constructed on the basis of RISC-processors of two types PowerPC and P2SC (POWER2 Super Chip). The servers c by the processor PowerPC have the internal architecture PCI and ideally approach for usage on any sites of designer activity. An example of such system is a series of inexpensive workstations 7043-43P (model 140 and 240).

   If you need to increase productivity of your system for usage of more complex(difficult) mathematical methods, such as “ a Method of a finite element ”, or to lead(carry out) account of the control program for the machine tool from a PNC, in this case RS/6000 the model 7013-397 completely will satisfy your needs(requirements). The given model is constructed on the basis of the processor POWER2 Super Chip 160 ĚĂö and microchannel architecture and is used for solution đĺńóđńîĺěęčő of the tasks.

   All workstations äâîč÷íî are compatible at a level of an operating system, that provides protection nested with you of resources in the software, allowing to use programs without changes on all set RS/6000.

   The workstations RS/6000 reach(achieve) high efficiency by operation with the graphics applications, combining power of the processor with a wide spectrum of graphics adapters permitting to work as with 2D-objects of an initial level, and with complex(difficult) 3D-object.s IBM also offers the widest support 3D API in the market of UNIX-systems. So, the system of processing of graphic datas OpenGL is included into the standard package of an operating system AIX, which, in turn, is delivered free-of-charge with systems RS/6000.

   Depending on what task you decide(solve), there is a whole spectrum of graphics accelerators intended for usage with 2D and the complex(difficult) three-dimensional data. For example, the graphics accelerator POWER GXT250P provides leading productivity for models 43Đ by operation with the 2D-applications. The graphics accelerator POWER GXT500P, intended for operation with a three-dimensional graphics, provides high efficiency, which grows according to growth of power of the processor.

   October 6, 1997 IBM has declared about the release of a number of new workstations and servers RS/6000 for technical calculations, which are intended for rise of productivity of work in the field of science, engineering and designing. The new resources for not accepting failures (mission critical) technical calculations will allow the users more effectively to use the complex(difficult) applications in a number of the graphics environments. Into number of the declared new products enter:

   1. Model 43P 140 332 ĚĂö: modernization of a popular series of workstations 43P;
   2. Model 397: a new workstation on the basis of a chip POWER2 Super Chip (P2SC);
   3. P2SC 160 ĚĂö: more high-efficiency “thin” site (thin Node) for RS/6000 SP;
   4. POWER GXT120P: modification of the graphics accelerator GXT110P;
   5. POWER GXT 800M: the powerful graphics accelerator;
   6. Compact discs with new user environments for RS/6000.
   1. Model 43P 140 332 ĚĂö

   The growth of computational capability of model 140 of a series 43P at the expense of rise of clock rate up to 332 ĚĂö results in further increase of the superiority of products, offered for technical calculations, RS/6000 on a metric “price / productivity”. The computers of a series 43P are ideal for the applications of computer-aided design of mechanical sites (MCAD — mechanical computer-aided design), in which the extremely necessary acceleration of account of geometry is directly connected to speed of operation of the processor. At installation of the accelerator GXT800P the users of the application of computer-aided design CATIA can expect a scoring in productivity at 20-25 of %.

   2. Model 397

   The new model 397 of a workstation RS/6000 gives possibilities for realization of bulky numerical accounts. Productivity on floating-point operations (SPECfp95 25.8) and extremely large bandwidth of memory do(make) by its(her) leader of branch. These characteristics of model allow the engineers and scientist (for example, occupied the calculator íîé ăŕçî- and hydrodynamics or learning of influence of the external factors — of an electricity, air and temperature — on a construction of the automobile or wings of the plane) to achieve effective operation of the large, complex(difficult) applications. The processor, used in this model, POWER2 Super Chip (P2SC) is capable to fulfil mipses. The large passband of the bus allows the users simultaneously to work above the several projects. The same processor, as in model 397, is used in RS/6000 SP, supercomputer known under the name Deep Blue, which has won 1997 in a chess match Ăŕđđč Ęŕńďŕđîâŕ.

   3. P2SC 160 ĚĂö

   New P2SC Thin Node (the “thin” site) with clock rate 160 ĚĂö for SP has on 25 % the large productivity on floating-point operations and twice high capacity of the internal disk (internal disk capacity), than now in use “thin” site with clock rate 120 ĚĂö. These characteristics allow to achieve optimal productivity at execution of the technical applications, such as investigation of petroleum, designing and analysis of mechanical sites.

   4. POWER GXT120P

   Modification of the graphics accelerator GXT110P. The new accelerator GXT120P, made IBM, strengthens positions RS/6000 on a metric “price / productivity” in the market of graphics resources of an initial level even more.

   5. POWER GXT 800M

   The accelerator GXT800M increases possibilities of a three-dimensional graphics of model 397 and existing number of workstations of model 595. For the score is hardware of the realized acceleration of mapping of texture (texture mapping) GXT800M gives on speeds, characteristic for the interactive mode, more realistic maps. His(its) 24-bit accelerator with double-buffer realizing the colour graphic palette True Colour, well supplements high efficiency of models 397 and 595 on floating-point operations.

   6. Compact discs with new user environments RS/6000

   Made IBM the compact discs with new user environments RS/6000 (facilitate one — for CATIA 4.1.8 under AIX 4.3, and another — for I-DEAS 5.0 under AIX 4.1.5) installation of the applications and provide simple îíëŕéí-access to the current information on products of the suppliers of the software and IBM RS/6000. Earlier declared IBM the compact disc Pro/Engineer will receive further development and will be issued again in 1998.

   Made IBM the resources for technical calculations are used by carrying on universities and corporations for support of the greater feedback from expenses for scientific researches, designing and development of production. Largest in the world the telescope officially open recently by University of staff(state) of Texas, was constructed with usage of workstations RS/6000 and package of computer-aided design CATIA. As a result of an expense for creation of a telescope were limited one sixth from cost of similar telescopes.

   Other example of usage of the technology IBM are the schedules of government of USA on creation of the automobile with more effective utilization of fuel, smaller ejection of harmful substances and share of components accepting processing, equal 80 %, with the help of the supercomputer RS/6000 SP. It is expected, that this automobile will cost no more, than standard automobiles made by other corporations. RS/6000 SP will make possible(probable) fast digital simulation and creation of the prototypes of materials used during designing of the automobile.

   The unique architecture of the ěŕńńčâíî-parallel system RS/6000 SP, constructed on the basis of the high-speed network (150 Máčň/c), joining up to 512 sites (systems RS/6000, fulfilled in special ęîíńňđóęňčâĺ), allows successfully to fulfil ńëîćíĺéřčĺ mathematical accounts for such tasks, as nonlinear simulation, for example simulation of the process of corrupting (crash simulation) or creation of the large repositories (data warehouse).

The list of the used literature

1. CAD and graphics. A chapter đĺä. Ęđŕńęîâńęčé Ä.Ă. M.: ĘîěďüţňĺđĎđĺńń, 1997
2. Theoretical bases of a CAD. Ęîđ˙÷ęî Â.Ď. M.: mechanical engineering, 1990.
3. www.klondike.ru
4. www.digital.com
5. www.ibm.com
6. www.sgi.com

Contents

I. Introduction

II. Aspects of choice of a workstation

A. Loading a kernel and units of the system

B. Recalculation of geometrical changes of model

C. Visualization of model

III. The browse of the market of workstations