Processors Performance

Assume that we have a program we will run on np processors and that this program has a serial portion and a parallel portion. For example, the serial portion of the code might read in input and calculate certain global parameters. It does not make any difference if this work is done on one processor and the results distributed, or if each processor performs identical tasks independently this is essentially serial work. Then the time t it takes the program to run in serial on one processor is the sum of the time spent in the serial portion of the code and the time spent in the parallel portion (i.e., the portion of the code that can be parallelized) is t = tg + tp. Amdahl s law defines a parallel efficiency, Pe, of the code as the ratio of total wall clock time to run on one processor to the total wall clock time to run on np processors. We give a formulation of Amdahl s law due to Meijer [42] ... 

In working through process control examples, we found that many calculations, data checks, rate checks and other computationally intensive tasks are done at the first level of inference. Considerations of computational efficiency led to a design utilizing two parallel processors with a shared memory (Figure 1). One of the processors is a 68010 programmed in C code. This processor performs computationally intensive, low level tasks which are directed by the expert system in the LISP processor. 

Table 2. Battelle Subwatt Power Microscale Fuel Processor Performance ...

Recent fuel processor performance is summarized in Table 4. The fuel processors were operated at atmospheric pressure, and the water and methanol feed mixture was about 60 wt % methanol. The typical composition of the reformate stream was 72— 74% hydrogen, 24—26% carbon dioxide, and 0.5—1.5% carbon monoxide on a dry gas basis. The carbon monoxide levels were significantly below equilibrium (5.4% at 350 °C), but they still require additional cleanup for use in fuel cells. The fuel processor efficiency was calculated using eq 5 and was reported to be greater than 80%. It is interesting to note that increasing the power 5-fold, from 20 to 100 W, only resulted in a 50% increase in volume and a 33% increase in mass. 

Floating Point. Integrated floating point units first arrived as separate coprocessors under the direct control of the microprocessor. However, these processors performed arithmetic with numerous sequential operations, resulting in performance too slow for real-time signal processing. 

Micro structured heat exchanger reactors offer unique capabilities of improving fuel processor performance as described in the sections above. However, manufacturing costs are currently considerably higher than for conventional mature technology. This will be overcome in the future with the application of cheap manufacturing and coating techniques suitable for mass production (see Sections 2.9 and 2.10), a procedure which is currently underway. 

Hardware floating-point processor Performs with very high speed floating-point arithmetic operations and expands tremendously the computational speed of the machine. 

Time levels of graphics workstation have come into use over the last few years. The low-end systems typically have 2 to 5 MIPS of processor performance, numeric computing performance of 0.25 to 1 MFLOPS, and a drawing performance of 200,000 v/s and 2,000 to 5,000 p/s. Many of these systems were developed around the Motorola 68020 processor with a floating point processor. Since they are created from off-the-shelf components, they are relatively inexpensive ( 10,000 to 30,000). They are adequate when used for small molecule (250 atoms or less) calculations and interactive display. 

Unless motor memory capacities are being tested, the responder is typically chosen to minimize stress on motoric processing and, compared to processor performance measures, not to isolate a unique motor memory system. 

Image processing and analysis often require fixed sequences of local operations to be performed at each pixel of an image. Such sequences of operations can be performed in parallel using a pipeline of processors, each operating on the output of the preceding one. The first processor performs the first operation on the image, pixel by... 

Pipeline architecture A computer architecture that employs time-sequential parallelism rather than spatial parallelism. That is, the input data is time sequenced, and each processor performs one portion of the total operation on each piece of data in time sequence. 

Commercial workloads have been shown to have dramatically different behavior compared to scientific and engineering workloads (Barroso et al., 1998 Keeton et al., 1998). Due to the fraction of time spent in the memory system and lack of instruction-level paraUehsm, there is a relatively small gain from improving integer processor performance (also, there is no floating-point computation). Commercial applications also make frequent use of operating system services and I/O, making the performance of system software more important. 

S. Y. Kung. Systolic array processors performance analysis and design optimization, chapter 4.4, pages 226-248. Prentice Hall, 1988. 

For EB curing/ the important processing parameters are the beam current 1 / the voltage V, and the product speed S. E-B processor performance is characterized by the yield factor (k) / which relates V, and S through the dosage/... 

Precolored compounds are delivered ready for final processing. Prior to delivery to the extruder, they have been mixed to the final ratio of polymer to colorant. This is the easiest form in which to color polymer because it requires no additional materials or hardware other than what is typical for single-material extrusion. Additionally, the imiformity of color is usually excellent as a result of the compounding process. However, this form is generally expensive because another processor performs the compounding work. 

During the last few deeades there have been a number of eontinuing and emerging trends in embedded systems in relation to safety, seeurity and performanee. Some of these trends have progressed independently of each oflier, whilst others appear to be inter-related, such as the increase in processor performance enabling multiple applications to be hosted concurrently on the same processor, which has certification implications in a safety-critical environment... 

However, this is not the end of the matter, because the 1.6 times increase in processor performance does not necessarily mean that an application will run 1.6 times faster. This is due to the fact that in order to exploit the performance of the dual cores, the application needs to exhibit sufficient parallelism so that different parts of the application can run concurrently on each core. In general, the parallel speedup which can be achieved with multiple processors (or cores) is determined by the portion of the application which must be executed sequentially. This is known as Amdahl s Law (Amdahl 1967), which can be expressed formally as the... 

The I/O device became a controller of the peripheral device, but the processor performed the programmed I/O (the processor stopped processing other instructions until the I/O activity had completed and the device had signaled its completion of the required action). 

An 8-bit field is more than sufficient, in most cases, to specify a particular processing action. There are times, however, when execution of the instmction code requires more information than 8 bits can convey. One example of this is when the instmction references a memory location. The basic instmction code identifies the operation to be performed, but it cannot also specify the object address. In a case such as this, a two-word instmction must be used. Successive instmction bytes are stored in sequentially adjacent memory locations, and the processor performs two fetches in succession to obtain the full instmction. The first byte retrieved from memory is placed in the processor s instmction register, and the second byte is placed in temporary storage, as appropriate. When the entire instmction is fetched, the processor can proceed to the execution phase. 

Processors perform both read and write cycles. The data lines Di can be multiplexed if the outputs are three-stated when not selected. Two separate WRS and RDS lines, never activated simultaneously, can control the transfer (Fig. 2c). This solution is preferred by several manufacturers and used, for example, on the early IBM-PC bus. 

Fig. 14.9 Fuei processor performance during ioad transients [61]...

Design 2 consists of 2 processors pia - a processor of type pi, and paa -a processor of type pa- Processor p a performs subtasks S and 54 in that order, and processor paa performs subtasks 52 and 5a in that order. There is a communication link lu,3a- Data ia,i gets transmitted on link ha,3a-Design 3 consists of just 1 processor p2a - a processor of type p2- The processor performs the subtasks 52, 5i, 54, and 5a in that order. 

In Figure 1 the first row of boxes indicates the overall concepts which the user must keep in mind an interface implemented as a pair of pre- and post-processors performs the translation between the product data representations in CAD systems and the neutral file. The second row represents the formal specification contained in this book the neutral file grammar which is specified in BNF productions, the semantical interpretation of a neutral file (defined as a finite state machine) in order to build a data structure which is compatible with the reference model specified. The last row shall indicate that validity of a neutral file requires conformance with the grammar, validity of the post-processor requires conformance with the semantic specification, and finally that CAD system data base contents can... 

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