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	MASSIVELY PARALLEL TECH MATHEMATICALLY DERIVES AMDAHL'S LAW
		Amdahl's Law, though never before proven through a mathematical derivation from first principles, helped establish the supercomputing industry and has for more than 30 years been a force in the industry.
		Gene Amdahl, a recognized authority on parallel processing, crafted "Amdahl's Law" in 1967, which states that there are communication issues that eventually place an upper limit on the maximum speed of parallel processing systems, therefore mitigating much of the benefit of parallelization.
		For 35 plus years, traditional non-mathematic interpretations of Amdahl's Law have led developers of supercomputers to believe that only 20 percent or less efficiency was possible through parallel processing, with larger machines achieving only 7 percent to 10 percent efficiency.
	www.hpcwire.com /hpc/328050.html (458 words)

	Amdahls law - Amdahls law
		Amdahl's law, named after computer architect Gene Amdahl, is used to find out the maximum expected improvement to an overall system when only a part of the system is improved.
		Amdahl's law is a demonstration of the law of diminishing returns: while one could speed up part of a computer a hundred-fold or more, if the improvement only affects 12% of the overall task, the best the speedup could possibly be is times faster.
		More technically, the law is concerned with the speedup achievable from an improvement to a computation that affects a proportion P of that computation where the improvement has a speedup of S.
	www.infotechloco.com /Inf-Computer-Topics-A---B/Amdahls-law.html (0 words)

	Amdahl's law - Wikipedia, the free encyclopedia
		Amdahl's law, named after computer architect Gene Amdahl, is used to find the maximum expected improvement to an overall system when only part of the system is improved.
		Amdahl's law can be interpreted more technically, but in simplest terms it means that it is the algorithm that decides the speedup not the number of processors.
		Amdahl's law is a demonstration of the law of diminishing returns: while one could speed up part of a computer a hundred-fold or more, if the improvement only affects 12% of the overall task, the best the speedup could possibly be is
	en.wikipedia.org /wiki/Amdahl's_law (828 words)

	Amdahl’s law describes the maximum speedup that can be expected from code being parallelized over multiple processors (Site not responding. Last check: 2007-10-10)
		Amdahl’s law describes the maximum speedup that can be expected from code being parallelized over multiple processors
		Amdahl’s law (Equation 1) describes the maximum speedup (ignoring super-linear cases) that can be expected from any code being parallelized over multiple processors, given the parallelizable fraction of the
		Amdahl’s law can also provide insight into an unknown fraction of a particular code that has been parallelized, assuming at least two times-to-solution are known for different processor counts and assuming perfect scalability.
	www.arl.army.mil /main/Main/DownloadedInternetPages/CurrentPages/StudentandFacultyPrograms/reports/schwartz.htm (1007 words)

	amdahls law at parrosantaperpe.info (Site not responding. Last check: 2007-10-10)
		Amdahl's law named after computer architect Gene Amdahl is used to find out the maximum expected sped up x so S Amdahls law or P is Amdahl's law.
		Amdahl's law named after computer architect Gene Amdahl is used Amdahl's law can be interpreted more technically but in simplest Amdahls law.
		Amdahl's law named after computer architect Gene Amdahl is used Amdahl's law can be interpreted more technically but in simplest Online shopping from a great selection of Browse Books Subjects and more at everyday low prices.
	law.parrosantaperpe.info /amdahls-law.html (0 words)

	Amdahl Law - Beyond3D Forum
		Amdahl's law might not even apply at all really, depending on how the code is set up to work.
		The 'B' in Amdahl's law is tremendously algorithm-dependent; the algorithms that e.g.
		Amdahl may have been pessimistic about certain elements of performance, but that does not change the fact that the law has yet to be broken.
	www.beyond3d.com /forum/showthread.php?p=651048 (0 words)

	Embedded.com - What Amdahl's Law can tell us about multicores and multiprocessing
		Simply stated, Gene Amdahl’s law of parallel computing states that the speedup of a parallel algorithm is limited by the fraction of the problem that must be performed sequentially; that is, your design is only as strong as its weakest link.
		Amdahl’s Law of parallel computing assumes that no matter how many processing units are available, a sequential portion of the code may need to be executed.
		The notion of speedup as defined in Amdahl’s Law relates to fixed size tasks, or when the mean to maximum execution time approaches unity, defined earlier as the optimal task balancing case.
	www.embedded.com /showArticle.jhtml?articleID=173603024 (1850 words)

	Rico Mariani's Performance Tidbits : Amdahl's Law : Big Speedups From Bigger Fractions
		That's probably how most people think about Amdahl's law -- if you're working on some code the best improvement you can hope to get is what the speed would be if the part you're working on was completely removed.
		Well, in terms of Amdahl's Law, I think of it this way: The fraction of the total work that I am improving is often much bigger than it appears.
		The assumption is correct, not as a law but a useful generalization: it is rare that portion of the code with 4% running time has a bigger perf impact than something with 30 or more %.
	blogs.msdn.com /ricom/archive/2005/12/16/504800.aspx (1303 words)

	Amdahls Law (Site not responding. Last check: 2007-10-10)
		Proposed in 1967, Amdahls' Law examines the theoretical maximum speedup obtained by using parallel processing.
		This "Law" has been re-evaluated since and its underlying assumptions challenged.
		Amdahl's Law: If ts is the run time and f its parallelizable fraction, with n cpu's, the total time tt becomes:
	c2.com /cgi/wiki?AmdahlsLaw (267 words)

	Factors That Limit Speedup
		Therefore Amdahls Law tells us that the serial fracrion F places a severe constraint on the speedup as the number of processors increase.
		Since most parallel programs contain a certain amount of sequential code, a possible conclusion of Amdahls Law is that it is not cost effective to build systems with large numbers of processors because sufficient speedup will never be produced.
		Amdahls Law is valid for problems in which the serial fraction F does not vary with the problem size
	www.cs.cf.ac.uk /Parallel/Year2/section7.html (1378 words)

	Amdahl's Law
		We now have timing results for a 1024-processor system that demonstrate that the assumptions underlying Amdahl's 1967 argument are inappropriate for the current approach to massive ensemble parallelism.
		We feel that it is important for the computing research community to overcome the "mental block" against massive parallelism imposed by a misuse of Amdahl's speedup formula; speedup should be measured by scaling the problem to the number of processors, not fixing problem size.
		Amdahl, G.M. Validity of the single-processor approach to achieving large scale computing capabilities.
	www.scl.ameslab.gov /Publications/Gus/AmdahlsLaw/Amdahls.html (612 words)

	Amdahl's Law (Site not responding. Last check: 2007-10-10)
		Amdahl's Law is a law governing the speedup of using parallel processors on a problem, versus using only one serial processor.
		Before we examine Amdahl's Law, we should gain a better understanding of what is meant by speedup.
		When B is constant (recall B = the percentage of the strictly parallel portion of the program), Amdahl's Law yields a speedup curve which is logarithmic and remains below the line S=N. This law shows that it is indeed the algorithm and not the number of processors which limits the speedup.
	home.wlu.edu /~whaleyt/classes/parallel/topics/amdahl.html (474 words)

	Reevaluating Amdahl's Law and Gustafson's Law (Site not responding. Last check: 2007-10-10)
		Researchers in the parallel processing community have been using Amdahl's Law and Gustafson's Law to obtain estimated speedups as measures of parallel program potential.
		The key to Amdahl's Law is a serial processing percentage relative to the overall program execution time using a single processor.
		This is often referred to as the Gustafson's Law [5] and has been widely refereed to as a "scaled speedup measure".
	www.cis.temple.edu /~shi/docs/amdahl/amdahl.html (2909 words)

	Performance: Understanding Amdahl's Law ...
		Amdahl's law (for the scope of this tip) calculates the magnitude of theoretical speed improvements that can be achieved for a given process by having more concurrent processors available(or parallelism).
		To calculate the improvements with Amdahl's law, we need one other value, typically referred to as the 'sequential' or 'serial' fraction (and usually denoted by 'F').
		It's not common to apply Amdahl's law directly anyway; instead it's really a matter of understanding what it means about points of contention, and applying those rules in your application architecture and deployment.
	www.javalobby.org /java/forums/t84101.html (1056 words)

	Take charge of processor affinity
		Amdahl's Law governs the speedup of using parallel processors on a problem versus using only one serial processor.
		Amdahl's Law states this probably won't happen in reality, but the closer the better.
		Amdahl's Law is especially important when you want to keep the CPU cache hit rate high.
	www-128.ibm.com /developerworks/linux/library/l-affinity.html (1819 words)

	ClusterMonkey - Understanding Amdahl's Law (Site not responding. Last check: 2007-10-10)
		Amdahl observed that many programs could be at least partially parallelized, that is, part of the work that they did could be split up and one on more than one system at a time.
		Amdahl's Law is very important as it makes it clear that when engineering a cluster the best you can hope for is getting your work done N times as fast on an N CPU (Central Processing Unit) cluster.
		At this point you are pretty close to knowing enough of the fundamentals of parallel computing to hold your own in a discussion over a beer at a geek supercomputer meeting such as Supercomputing.
	www.clustermonkey.net /content/view/79/32 (1443 words)

	Amdahl's Law
		IBM (which made just about all computers at the time and for a considerable time afterward) wanted to speed things up by doing things in parallel (to sell more computers), but rapidly found that there were some fairly stringent restrictions on how much of a speedup one could get for a given parallelized task.
		Amdahl's law, we must begin by defining the ``speed'' of a program.
		Since we're going to derive complicated variants of this law (that are much better approximators to the speedup bounds) we'd better see how this is derived.
	www.phy.duke.edu /~rgb/Beowulf/beowulf_book/beowulf_book/node21.html (1346 words)

	Parallelizing Sun ANSI/ISO C Code
		Fixed problem-size speedup is generally governed by Amdahl's law.
		Amdahl's Law simply says that the amount of parallel speedup in a given problem is limited by the sequential portion of the problem.The following equation describes the speedup of a problem where F is the fraction of time spent in sequential region, and the remaining fraction of the time is spent uniformly among P processors.
		Amdahls Law can be misleading for predicting parallel speedups in real problems.
	docs.sun.com /source/806-3567/parallel.html (6246 words)

	Scalable Amdahl's Law
		This a much more encouraging picture than Amdahl's Law suggested.
		In summary, Amdahl's Law tells us that we get miserable performance unless most of the operations are vectorization.
		Scalable Amdahl's Law tells us that for certain types of problems, most of the operations are vectorizable, so that performance is near optimal.
	www.ma.iup.edu /~hedonley/ma451/samdahl.html (293 words)

	computer repair
		Early examples of workstations were generally cheap minicomputers; a system of interest it performs /analysis/ and seeks general principals to explain that system.
		As with all highly parallel systems, computer repair watford Amdahls law applies, computer maintenance repair and supercomputer designs devote great effort to eliminating software serialization, and using hardware to accelerate the remaining bottlenecks.
		As with all highly parallel systems, atlanta computer repair Amdahls law applies, and supercomputer is a computer program.
	computer-repair.bestmoment.org (2539 words)

	AMDAHL'S LAW FOR PARALLEL SPEEDUP
		To see real gains, q must be closer to 0.9 or 0.95, fractions that are difficult to obtain.
		Moreover, Amdahl's Law as presented ignores many of the realities of computing.
		Among the idealizations we ahve made are (i) parallelization is free, communication is free; (ii) parallel operation is a multiple of sequential operation, without changing data structures or operational design.
	www.math.buffalo.edu /~pitman/courses/cor501/HPC1/node11.html (310 words)

	[No title] (Site not responding. Last check: 2007-10-10)
		Subject: Amdahl's law and superlinear speedup (summary of answers) Date: Thu, 27 Oct 94 14:42:17 MET Organisation: iXOS Software GmbH A few days ago, I posted a query about Amdahl's law to comp.parallel.
		Each local event queue > now has (on the average) log2(n/N) performance and because each of the nodes > are using their event queues in parallel, the overall event list management > goes like (1/N)log2(n/N) which has superlinear speedup.
		Some have thought that > this is mysterious and that the laws of common sense in parallel computing > are violated.
	phase.hpcc.jp /mirrors/parallel/faqs/amdahls-law (0 words)

	Report on CCSM Software Engineering Working Group Meeting, 25 June 2002
		Commodity hardware is currently plagued problems in system balance where the processor performance is relatively greater that the memory access or interconnect performance.
		Processor improvement continues to follow Amdahls law while the memory access and interconnect are improving slower, so unbalanced systems will continue to be a problem on non-custom hardware.
		Finally, a consensus developed that it was very difficult to write software that was flexible enough to take advantage of both vector and cache based systems.
	www.cgd.ucar.edu /csm/working_groups/Software/reports/020625.html (0 words)

	Wither Those Tiers
		Scaling a three-tier architecture is not an obvious task, however.
		To paraphrase, Amdahls's Law, a system scales only to the degree its weakest link scales.
		As more clients access the presentation tier, if those presentation requests must also access the business logic tier, the business logic tier must also scale along with the presentation tier.
	www.artima.com /weblogs/viewpost.jsp?thread=159087 (2230 words)

	Ace's Hardware
		This probably explains why the Pentium 4 1.5 GHz is scoring so low on this benchmark.
		The Athlon can hardly show his FPU muscles with less than 25% FP operations (Amdahls Law), and we all know that the Athlon's predictor is hardly better than the PIII's.
		The mystery has been solved why the tripple FPU (Athlon) did not walk over the single FPU (PIII), while it succeeded to do so in Flops.
	www.aceshardware.com /read_news.jsp?id=20000295 (0 words)

	Massively Parallel Technologies Mathematically Derives Amdahl's Law
		Company Makes Supercomputing Faster and Cheaper Than Ever Before LOUISVILLE, Colo., Jan. 18 /PRNewswire/ -- Massively Parallel Technologies (MPT), a provider of on-demand high-performance computing, announced the company has developed the first mathematical derivation of Amdahl's Law.
		The sky's the limit." Massively Parallel Technologies co-founder and chief technology officer Kevin Howard surprised Dr. Amdahl with the first mathematical derivation of Amdahl's Law at a recent gathering at the company's headquarters in Louisville, Colorado.
		Dr. Amdahl's foresight is simply astonishing." About Massively Parallel Technologies, Inc. Massively Parallel Technologies (MPT), a Colorado-based company, delivers high-performance computing through Virtual Power Centers(TM), Internet-based hubs designed for specific computationally intense applications.
	www.prnewswire.com /cgi-bin/stories.pl?ACCT=109&STORY=/www/story/01-18-2005/0002859298&EDATE= (973 words)

	R5-2 < Fall2004 < TWiki (Site not responding. Last check: 2007-10-10)
		LRPC has a mix of capability and RPC systems.LRPC follows Amdahl's law principle of common-case faster approach by avoiding needless scheduling, unnecessary access validation and redundant copies.
		Given it is optimized for the same-machine case, it reduces the cost of cross-thread message passing to close to the hardware-imposed limit.
		--Optimizes for the common case (the takehome lesson of Amdahl's Law).
	srg.cs.uiuc.edu /twiki/bin/view/Fall2004/R5-2 (0 words)

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