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60-417: STAR is a blend of ST rings (of binary digits) and AR rays. The 100 alludes to the nominal peak processing speed of 100 million floating point operations per second ( MFLOPS ); the earlier CDC 7600 provided peak performance of 36 MFLOPS but more typically ran at around 10 MFLOPS. The design was part of a bid made to Lawrence Livermore National Laboratory (LLNL) in the mid-1960s. Livermore

120-425: A Speedup optimized {\displaystyle {\text{Speedup}}_{\text{optimized}}} of 10,000, then Speedup overall {\displaystyle {\text{Speedup}}_{\text{overall}}} becomes 1.11 which means only 11% improvement in total speedup of the program. So, despite a massive improvement in one section, the overall benefit is quite small. In another example, if

180-426: A compound , which fully preserves the stems of the original words. The British lecturer Valerie Adams's 1973 Introduction to Modern English Word-Formation explains that "In words such as motel ..., hotel is represented by various shorter substitutes – ‑otel ... – which I shall call splinters. Words containing splinters I shall call blends". Thus, at least one of the parts of a blend, strictly speaking,

240-523: A form suitable for carrying on horseback; (now esp.) one in the form of a stiff leather case hinged at the back to open into two equal parts". According to The American Heritage Dictionary of the English Language ( AHD ), the etymology of the word is the French porte-manteau , from porter , "to carry", and manteau , "cloak" (from Old French mantel , from Latin mantellum ). According to

300-451: A fraction of its theoretical performance for a number of reasons. Firstly, the vector instructions, being "memory-to-memory," had a relatively long startup time, since the pipeline from the memory to the functional units was very long. In contrast to the register-based pipelined functional units in the 7600, the STAR pipelines were much deeper. The problem was compounded by the fact that the STAR had

360-427: A kind of bath), the attributive blends of English are mostly head-final and mostly endocentric . As an example of an exocentric attributive blend, Fruitopia may metaphorically take the buyer to a fruity utopia (and not a utopian fruit); however, it is not a utopia but a drink. Coordinate blends (also called associative or portmanteau blends) combine two words having equal status, and have two heads. Thus brunch

420-446: A single instruction could add two variable-length vectors of up to 65,535 elements with just one instruction fetch. The STAR also fetched vector operands in 512-bit units (superwords), reducing average memory latency. Since the memory location of the "next" operand is known, the CPU can fetch the next operands while it is operating on the previous ones. As with instruction pipelines in general,

480-481: A single part of a system is limited by the fraction of time that the improved part is actually used". It is named after computer scientist Gene Amdahl , and was presented at the American Federation of Information Processing Societies (AFIPS) Spring Joint Computer Conference in 1967. Amdahl's law is often used in parallel computing to predict the theoretical speedup when using multiple processors. In

540-416: A slower cycle time than the 7600 (40 ns vs 27.5 ns). So the vector length needed for the STAR to run faster than the 7600 occurred at about 50 elements; if the loops were working on data sets with fewer elements, the time cost of setting up the vector pipeline was higher than the time savings provided by the vector instruction(s). When the machine was released in 1974, it quickly became apparent that

600-481: A total blend, each of the words creating the blend is reduced to a mere splinter. Some linguists limit blends to these (perhaps with additional conditions): for example, Ingo Plag considers "proper blends" to be total blends that semantically are coordinate, the remainder being "shortened compounds". Commonly for English blends, the beginning of one word is followed by the end of another: Much less commonly in English,

660-411: Is frankenword , an autological word exemplifying the phenomenon it describes, blending " Frankenstein " and "word". Amdahl%27s Law In computer architecture , Amdahl's law (or Amdahl's argument ) is a formula that shows how much faster a task can be completed when you add more resources to the system. The law can be stated as: "the overall performance improvement gained by optimizing

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720-477: Is a Japanese blend that has entered the English language. The Vietnamese language also encourages blend words formed from Sino-Vietnamese vocabulary . For example, the term Việt Cộng is derived from the first syllables of "Việt Nam" (Vietnam) and "Cộng sản" (communist). Many corporate brand names , trademarks, and initiatives, as well as names of corporations and organizations themselves, are blends. For example, Wiktionary , one of Misplaced Pages 's sister projects,

780-489: Is a blend of wiki and dictionary . The word portmanteau was introduced in this sense by Lewis Carroll in the book Through the Looking-Glass (1871), where Humpty Dumpty explains to Alice the coinage of unusual words used in " Jabberwocky ". Slithy means "slimy and lithe" and mimsy means "miserable and flimsy". Humpty Dumpty explains to Alice the practice of combining words in various ways, comparing it to

840-515: Is better than making part B to run 5 times faster. The percentage improvement in speed can be calculated as If the non-parallelizable part is optimized by a factor of O {\displaystyle O} , then It follows from Amdahl's law that the speedup due to parallelism is given by When s = 1 {\displaystyle s=1} , we have S latency ( O , s ) = 1 {\displaystyle S_{\text{latency}}(O,s)=1} , meaning that

900-440: Is both phonological and orthographic, but with no other shortening: The overlap may be both phonological and orthographic, and with some additional shortening to at least one of the ingredients: Such an overlap may be discontinuous: These are also termed imperfect blends. It can occur with three components: The phonological overlap need not also be orthographic: If the phonological but non-orthographic overlap encompasses

960-692: Is neither a breakfasty lunch nor a lunchtime breakfast but instead some hybrid of breakfast and lunch; Oxbridge is equally Oxford and Cambridge universities. This too parallels (conventional, non-blend) compounds: an actor–director is equally an actor and a director. Two kinds of coordinate blends are particularly conspicuous: those that combine (near‑) synonyms: and those that combine (near‑) opposites: Blending can also apply to roots rather than words, for instance in Israeli Hebrew : "There are two possible etymological analyses for Israeli Hebrew כספר kaspár 'bank clerk, teller'. The first

1020-664: Is not a complete morpheme , but instead a mere splinter or leftover word fragment. For instance, starfish is a compound, not a blend, of star and fish , as it includes both words in full. However, if it were called a " stish " or a " starsh ", it would be a blend. Furthermore, when blends are formed by shortening established compounds or phrases, they can be considered clipped compounds , such as romcom for romantic comedy . Blends of two or more words may be classified from each of three viewpoints: morphotactic, morphonological, and morphosemantic. Blends may be classified morphotactically into two kinds: total and partial . In

1080-452: Is similar to a contraction . On the one hand, mainstream blends tend to be formed at a particular historical moment followed by a rapid rise in popularity. Contractions, on the other hand, are formed by the gradual drifting together of words over time due to them commonly appearing together in sequence, such as do not naturally becoming don't (phonologically, / d uː n ɒ t / becoming / d oʊ n t / ). A blend also differs from

1140-514: Is sped up 20 times, so s 3 = 20 , and the 4th part is sped up 1.6 times, so s 4 = 1.6 . By using Amdahl's law, the overall speedup is Notice how the 5 times and 20 times speedup on the 2nd and 3rd parts respectively don't have much effect on the overall speedup when the 4th part (48% of the execution time) is accelerated by only 1.6 times. For example, with a serial program in two parts A and B for which T A = 3 s and T B = 1 s , Therefore, making part A to run 2 times faster

1200-405: Is that it consists of (Hebrew>) Israeli כסף késef 'money' and the ( International /Hebrew>) Israeli agentive suffix ר- -ár . The second is that it is a quasi- portmanteau word which blends כסף késef 'money' and (Hebrew>) Israeli ספר √spr 'count'. Israeli Hebrew כספר kaspár started as a brand name but soon entered the common language. Even if the second analysis is the correct one,

1260-439: Is the execution of the part that benefits from the improvement of the resources that is accelerated by the factor s {\displaystyle s} after the improvement of the resources. Consequently, the execution time of the part that does not benefit from it remains the same, while the part that benefits from it becomes: The theoretical execution time T ( s ) {\displaystyle T(s)} of

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1320-460: The APL programming language; in particular, the concept of "control vectors" (vector masks in modern terminology), and several instructions for vector permutation with control vectors, were carried over directly from APL. The vector instructions operated on vectors that were stored in consecutive locations in main memory; memory addressing was virtual . The vector instructions fed an arithmetic pipeline ;

1380-520: The OED Online , the etymology of the word is the "officer who carries the mantle of a person in a high position (1507 in Middle French), case or bag for carrying clothing (1547), clothes rack (1640)". In modern French, a porte-manteau is a clothes valet , a coat-tree or similar article of furniture for hanging up jackets, hats, umbrellas and the like. An occasional synonym for "portmanteau word"

1440-565: The stream unit . The stream unit accesses the main memory through the SAC via three 128-bit data buses, two for reads, and one for writes. There is also a 128-bit data bus for instruction fetch, I/O, and control vector access. The stream unit serves as the control unit, fetching and decoding instructions, initiating memory accesses on the behalf of the pipelined functional units, and controlling instruction execution, among other tasks. It also contains two read buffers and one write buffer for streaming data to

1500-456: The 7600 to emulate the vector operations of the STAR. In the process of developing STACKLIB, they found that programs converted to use it ran faster than they had before, even on the 7600. This placed further pressures on the performance of the STAR. The STAR-100 was a disappointment to everyone involved. Jim Thornton , formerly Seymour Cray 's close assistant on the CDC 1604 and 6600 projects and

1560-462: The Amdahl's law and accounts for the additional overhead due to inter-process communication . USL quantifies scalability based on parameters such as contention and coherency. A task executed by a system whose resources are improved compared to an initial similar system can be split up into two parts: An example is a computer program that processes files. A part of that program may scan the directory of

1620-432: The STAR's generally complex architecture, was implemented with microcode . Main memory had a capacity of 65,536 512-bit words , called superwords (SWORDs). Main memory was 32-way interleaved to pipeline memory accesses. It was constructed from core memory with an access time of 1.28 μs. The main memory was accessed via a 512-bit bus, controlled by the storage access controller (SAC), which handled requests from

1680-512: The achieved speedup) what is to be improved, then one will see monotonically decreasing improvements as one improves. If, however, one picks non-optimally, after improving a sub-optimal component and moving on to improve a more optimal component, one can see an increase in the return. Note that it is often rational to improve a system in an order that is "non-optimal" in this sense, given that some improvements are more difficult or require larger development time than others. Amdahl's law does represent

1740-502: The beginning of one word may be followed by the beginning of another: Some linguists do not regard beginning+beginning concatenations as blends, instead calling them complex clippings, clipping compounds or clipped compounds . Unusually in English, the end of one word may be followed by the end of another: A splinter of one word may replace part of another, as in three coined by Lewis Carroll in " Jabberwocky ": They are sometimes termed intercalative blends; these words are among

1800-480: The case wherein the non-parallelizable part is reduced by a factor of O ′ {\displaystyle O'} , and the parallelizable part is correspondingly increased. Then It follows from Amdahl's law that the speedup due to parallelism is given by Amdahl's law is often conflated with the law of diminishing returns , whereas only a special case of applying Amdahl's law demonstrates law of diminishing returns. If one picks optimally (in terms of

1860-458: The cases where the problem size is fixed. In practice, as more computing resources become available, they tend to get used on larger problems (larger datasets), and the time spent in the parallelizable part often grows much faster than the inherently serial work. In this case, Gustafson's law gives a less pessimistic and more realistic assessment of the parallel performance. Universal Scalability Law (USL), developed by Neil J. Gunther , extends

CDC STAR-100 - Misplaced Pages Continue

1920-495: The chief designer of STAR, left CDC to form Network Systems Corporation . An updated version of the basic architecture was later released in 1979 as the Cyber 203 , followed by the Cyber 205 in 1980, but by this point systems from Cray Research with considerably higher performance were on the market. The failure of the STAR led to CDC being pushed from its former dominance in the supercomputer market, something they tried to address with

1980-433: The context of Amdahl's law, speedup can be defined as: Speedup = Performance (or execution time) for the entire task when enhancements are applied Performance (execution time) for the same task without those enhancements {\displaystyle {\text{Speedup}}={\frac {\text{Performance (or execution time) for the entire task when enhancements are applied}}{\text{Performance (execution time) for

2040-464: The disk and create a list of files internally in memory. After that, another part of the program passes each file to a separate thread for processing. The part that scans the directory and creates the file list cannot be sped up on a parallel computer, but the part that processes the files can. The execution time of the whole task before the improvement of the resources of the system is denoted as T {\displaystyle T} . It includes

2100-469: The execution time of the part that would not benefit from the improvement of the resources and the execution time of the one that would benefit from it. The fraction of the execution time of the task that would benefit from the improvement of the resources is denoted by p {\displaystyle p} . The one concerning the part that would not benefit from it is therefore 1 − p {\displaystyle 1-p} . Then: It

2160-414: The execution units. The STAR-100 has two arithmetic pipelines. The first has a floating point adder and multiplier, and the second can execute all scalar instructions. It also contains a floating point adder, multiplier, and divider. Both pipelines are 64-bit for floating point operations and are controlled by microcode. The STAR-100 can split its floating point pipelines into four 32-bit pipelines, doubling

2220-586: The final syllable ר- -ár apparently facilitated nativization since it was regarded as the Hebrew suffix ר- -år (probably of Persian pedigree), which usually refers to craftsmen and professionals, for instance as in Mendele Mocher Sforim 's coinage סמרטוטר smartutár 'rag-dealer'." Blending may occur with an error in lexical selection , the process by which a speaker uses his semantic knowledge to choose words. Lewis Carroll's explanation, which gave rise to

2280-535: The formation of ETA Systems in September 1983. Five CDC STAR-100s were built. Deliveries started from 1974: Blend word In linguistics , a blend —also known as a blend word , lexical blend , or portmanteau —is a word formed by combining the meanings, and parts of the sounds, of two or more words together. English examples include smog , coined by blending smoke and fog , as well as motel , from motor ( motorist ) and hotel . A blend

2340-451: The general performance was disappointing. Very few programs can be effectively vectorized into a series of single instructions; nearly all calculations will rely on the results of some earlier instruction, yet the results had to clear the pipelines before they could be fed back in. This forced most programs to pay the high setup cost of the vector units, and generally the ones that did "work" were extreme examples. Worse, basic scalar performance

2400-403: The ingredients is the head and the other is attributive. A porta-light is a portable light, not a 'light-emitting' or light portability; light is the head. A snobject is a snobbery-satisfying object and not an objective or other kind of snob; object is the head. As is also true for (conventional, non-blend) attributive compounds (among which bathroom , for example, is a kind of room, not

2460-428: The law of diminishing returns if one is considering what sort of return one gets by adding more processors to a machine, if one is running a fixed-size computation that will use all available processors to their capacity. Each new processor added to the system will add less usable power than the previous one. Each time one doubles the number of processors the speedup ratio will diminish, as the total throughput heads toward

CDC STAR-100 - Misplaced Pages Continue

2520-488: The limit of 1/(1 −  p ). This analysis neglects other potential bottlenecks such as memory bandwidth and I/O bandwidth. If these resources do not scale with the number of processors, then merely adding processors provides even lower returns. An implication of Amdahl's law is that to speed up real applications which have both serial and parallel portions, heterogeneous computing techniques are required. There are novel speedup and energy consumption models based on

2580-490: The morphemes or phonemes stay in the same position within the syllable. Some languages, like Japanese , encourage the shortening and merging of borrowed foreign words (as in gairaigo ), because they are long or difficult to pronounce in the target language. For example, karaoke , a combination of the Japanese word kara (meaning empty ) and the clipped form oke of the English loanword "orchestra" (J. ōkesutora , オーケストラ ),

2640-495: The original "portmanteaus" for which this meaning of the word was created. In a partial blend, one entire word is concatenated with a splinter from another. Some linguists do not recognize these as blends. An entire word may be followed by a splinter: A splinter may be followed by an entire word: An entire word may replace part of another: These have also been called sandwich words, and classed among intercalative blends. (When two words are combined in their entirety,

2700-404: The overall speedup of applying the improvement will be: For example, assume that we are given a serial task which is split into four consecutive parts, whose percentages of execution time are p 1 = 0.11 , p 2 = 0.18 , p 3 = 0.23 , and p 4 = 0.48 respectively. Then we are told that the 1st part is not sped up, so s 1 = 1 , while the 2nd part is sped up 5 times, so s 2 = 5 , the 3rd part

2760-402: The peak performance of the system to 100 MFLOPS at the expense of half the precision. The STAR-100 uses I/O processors to offload I/O from the CPU. Each I/O processor is a 16-bit minicomputer with its own main memory of 65,536 words of 16 bits each, which is implemented with core memory. The I/O processors all share a 128-bit data bus to the SAC. The STAR-100's real-world performance was

2820-401: The potential performance gain ( Speedup overall {\displaystyle {\text{Speedup}}_{\text{overall}}} will reach 100 if 100% of the execution time is covered) is lost due to the remaining 1% of execution time that was not improved. Followings are implications of Amdahl's law: Followings are limitations of Amdahl's law: Amdahl's law applies only to

2880-543: The programmer optimizes a section that accounts for 99% of the execution time (i.e. Time optimized {\displaystyle {\text{Time}}_{\text{optimized}}} of 0.99) with a speedup factor of 100 (i.e. Speedup optimized {\displaystyle {\text{Speedup}}_{\text{optimized}}} of 100), the Speedup overall {\displaystyle {\text{Speedup}}_{\text{overall}}} only reaches 50. This indicates that half of

2940-453: The result is considered a compound word rather than a blend. For example, bagpipe is a compound, not a blend, of bag and pipe. ) Morphologically, blends fall into two kinds: overlapping and non-overlapping . Overlapping blends are those for which the ingredients' consonants, vowels or even syllables overlap to some extent. The overlap can be of different kinds. These are also called haplologic blends. There may be an overlap that

3000-517: The same task without those enhancements}}}} Amdahl's law can be formulated in the following way: where The Speedup overall {\displaystyle {\text{Speedup}}_{\text{overall}}} is frequently much lower than one might expect. For instance, if a programmer enhances a part of the code that represents 10% of the total execution time (i.e. Time optimized {\displaystyle {\text{Time}}_{\text{optimized}}} of 0.10) and achieves

3060-424: The speedup is measured with respect to the execution time after the non-parallelizable part is optimized. When s = ∞ {\displaystyle s=\infty } , If 1 − p = 0.4 {\displaystyle 1-p=0.4} , O = 2 {\displaystyle O=2} and s = 5 {\displaystyle s=5} , then: Next, we consider

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3120-480: The then-common type of luggage , which opens into two equal parts: You see it's like a portmanteau—there are two meanings packed up into one word. In his introduction to his 1876 poem The Hunting of the Snark , Carroll again uses portmanteau when discussing lexical selection: Humpty Dumpty's theory, of two meanings packed into one word like a portmanteau, seems to me the right explanation for all. For instance, take

3180-417: The time needed to complete any one instruction was no better than it was before, but since the CPU is working on a number of data points at once, the overall performance dramatically improves. Many of the STAR's instructions were complex, especially the vector macro instructions, which performed complex operations that normally would have required long sequences of instructions. These instructions, along with

3240-462: The two words "fuming" and "furious". Make up your mind that you will say both words, but leave it unsettled which you will say first … if you have the rarest of gifts, a perfectly balanced mind, you will say "frumious". In then-contemporary English, a portmanteau was a suitcase that opened into two equal sections. According to the OED Online , a portmanteau is a "case or bag for carrying clothing and other belongings when travelling; (originally) one of

3300-406: The use of 'portmanteau' for such combinations, was: Humpty Dumpty's theory, of two meanings packed into one word like a portmanteau, seems to me the right explanation for all. For instance, take the two words "fuming" and "furious." Make up your mind that you will say both words ... you will say "frumious." The errors are based on similarity of meanings, rather than phonological similarities, and

3360-542: The whole of the shorter ingredient, as in then the effect depends on orthography alone. (They are also called orthographic blends. ) An orthographic overlap need not also be phonological: For some linguists, an overlap is a condition for a blend. Non-overlapping blends (also called substitution blends) have no overlap, whether phonological or orthographic: Morphosemantically, blends fall into two kinds: attributive and coordinate . Attributive blends (also called syntactic or telescope blends) are those in which one of

3420-421: The whole task after the improvement of the resources is then: Amdahl's law gives the theoretical speedup in latency of the execution of the whole task at fixed workload W {\displaystyle W} , which yields If 30% of the execution time may be the subject of a speedup, p will be 0.3; if the improvement makes the affected part twice as fast, s will be 2. Amdahl's law states that

3480-442: Was looking for a partner who would build a much faster machine on their own budget and then lease the resulting design to the lab. It was announced publicly in the early 1970s, and on 17 August 1971, CDC announced that General Motors had placed the first commercial order for it. A number of basic design features of the machine meant that its real-world performance was much lower than expected when first used commercially in 1974, and

3540-559: Was one of the primary reasons CDC was pushed from its former dominance in the supercomputer market when the Cray-1 was announced in 1975. Only three STAR-100 systems were delivered, two to LLNL and another to NASA Langley Research Center . The STAR had a 64-bit architecture , consisting of 195 instructions . Its main innovation was the inclusion of 65 vector instructions for vector processing . The operations performed by these instructions were strongly influenced by concepts and operators from

3600-525: Was sacrificed to improve vector performance. Any time that the program had to run scalar instructions, the overall performance of the machine dropped dramatically. (See Amdahl's Law .) Two STAR-100 systems were eventually delivered to the Lawrence Livermore National Laboratory and one to NASA Langley Research Center . In preparation for the STAR deliveries, LLNL programmers developed a library of subroutines , called STACKLIB , on

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