cpu performance equation derivation

Frequency of FP instructions : 25% Average CPI of FP instructions : 4.0 Average CPI of other instructions : 1.33 Frequency of FPSQR = 2% CPI of FPSQR = 20 Design Alternative 1: Reduce CPI of FPSQR from 20 to 2. … 20% of the dynamic instructions in an application are multiplies. Performance Equation - I CPU execution time = CPU clock cycles x Clock cycle time Clock cycle time = 1 / Clock speed If a processor has a frequency of 3 GHz, the clock ticks 3 billion times in a second – as we’ll soon see, with each clock tick, one or more/less instructions may complete If a program runs for 10 seconds on a 3 GHz processor, how many clock cycles did it run for? The equation would be: endobj In this dissertation we propose and investigate a new approach to CPU performance evaluation. 0000001291 00000 n 100% (3 ratings) The Processor Performance Equation is,CPUTime ,T= (Instruction Count* CPI) / Clock rate. For Intel Nehalem and AMD processors, Turbo is disabled by default on P-state-based platforms. since the clock rate is the inverse of clock cycle time: CPU time = Instruction count *CPI / Clock rate . The Classic CPU Performance Equation in terms of instruction count (the number of instructions executed by the program), CPI, and clock cycle time: CPU time=Instruction count * CPI * Clock cycle time or. The first step should be to find out the cycles per Instruction for P3. Relative performance: startxref Basic Performance Equation. x�b```f``Z�� Ā B�@��1&�( py��uN��8�q0�a�c0R��˰��R��1�A�A�AiSt��Nz:WX'1VH[#��`��Z�U��ˠh�t�q#�A��0��v CPU Performance Decomposed into Three Components: • Clock Frequency (φ ) … 1. Since around 2005–2007, Dennard scaling has ended, so even though Moore's law continued for several years after that, it has not yielded dividends in improved performance. The instruction count in the performance equation is the “dynamic”instruction count. The exponential processor transistor growth predicted by Moore does not always translate into exponentially greater practical CPU performance. %PDF-1.5 3-5 pipeline steps (ARM, SA, R3000) { Attempt to get C down to 1 { Problem: stalls due to control/data hazards Super-Pipelining { e.g. "��֤��4i��+ꀹ��ZqK��ҩ=M��~�ͼ�\��*G�� e맀 �w��o`�k�]��T�D�➳dۤ��`��%�@vl�� @6�R�``P�� L@Aa��1D�L C��`�8�\b��R�� *(��Jģ�E)4lR0��e�D��1��@'2)�F �J�`'�Ft40 endobj 0 † Instruction Count (IC) Determined by program, compiler, and ISA. Time reference in a computer is provided by a clock. Hydrological forecasting plays an important role in basin flood control systems, and the uncertainty of hydrological forecasting is helpful to reveal basin hydrological characteristics and provide support to decision makers in formulating water resources management schemes. CPI = average cycles per instruction. EE 4720 Lecture Transparency. Boussinesq’s 1872 paper introduces the equations now known as the x��O�0��#�ؾ��B�G41�R�p�s�d��L��k_��Z��g��Y��C! 1. 0000005828 00000 n Ic: Number of Instructions in a given program. The hydrologic uncertainty processor (HUP) has been widely employed in hydrological uncertainty prediction.  For example, with a base CPI of 1, the CPU time from the last page is: CPU time = (I+ 0.2 I) x Cycle time  What if we could doublethe CPU performance so the CPI becomes 0.5, but memory performance … 0000001375 00000 n Here, I = Total number instructions in a program. 7 0 obj T = clock cycle time. Put an X where the column heading can effect the row label. CPU time = (CPU execution cycles + Memory stall cycles) x Cycle time  Processor performance traditionally outpaces memory performance, so the memory system is often the system bottleneck. 0000002254 00000 n Derivation Of Performance Equation Consider a recycle reactor with nomenclature as shown in figure. T or R are usually published as performance measures for a processor. u� t��˳��&� ��[��z�Q�� 0000001647 00000 n �Oh��փ�}Ӭ}ӌ��>��j�_��&M��ʺA��v�г՟b�n\��jJ�Ԏ��Lh��HD"��}j��W��h��ű��+x�o��1�Z�x��4��c�E��i�wq�=��5G�Ji)�M�)��Gf�t6��#�J��nM��9��(�Ҥ057�l�S͎lx;��ȪA�F��6�G�uwt��J܇E%�x�dy��W��ܓ�"�I`T��V�.��W g��yFͻ��ox;��:"�z)��՛T��uJ}��ؔ� 0000000016 00000 n 02-2. CPU Clock Cycle (This equation is commonly known as the CPU performance equation) (executed, I) CPI = Cycles Per Instruction Executed (I) <> T = N X S / R . <> CPU Performance Equation: ACA- Lecture CPU Performance Equation: ACA- Lecture Execution Time (T): T: CPU time (seconds/program) needed to execute a program. The main idea is to represent machine performance and program execution in terms of a high level abstract machine model. … However, if a system supports Collaborative Processor Performance Control (CPPC), which is a new alternative mode of performance communication between the operating system and the hardware (defined in ACPI 5.0), Turbo may be engaged if the Windows operating system dynamically requests … † Clocks per Instruction (CPI) Determined by ISA, microarchitecture, compiler, and program. Gate coach faculty is explaining CRE topic- performance equation of CSTR. endobj <> <> 3. r%H�,��Ȃ^�i�+�. b. 8 0 obj 0000006733 00000 n A new processor cuts the CPI for multiplies from 10 to 5 but increases the cycle time by 10%. CPU Performance Decomposed into Three Components: † Clock Frequency (`) Determined by technology and in°uenced by organization. <>/Font<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 1024.08 768] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> xref extern INT8U ping; while(1) /* endless loop – spin in … 164 0 obj <> endobj %�� %PDF-1.4 %�� Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. ��2��~�*��;K)��ú��=��b��q�b��#a�ZZ5%د��5G7��1�5��RzMO�d��X��=�?U!�T@MYG4ӝ|� �v��#*��a�({�b=/�Y��XA��%\��ro��:L&ȴ��d�+�?H��K,�҇��5��׭��|�b̝�E��Fqr��=p>�)�d��jo��G��l��j��4�v��2��K��Ⱦ�?��7LSݬZb��F��v��ޝ��X��h�`r�p|��˷��dW�#�b!�D{�e� ��D�+��ky��I{��k��3 W\'2q�O�|ƞ`W��x\2��Gw�K�"i�UϏ��m��+��8��q�&�o�u��9$-�M�QJ֢eFx�� CPU Performance Equation - Pipelining A. Ardö, EIT Lecture 6: EITF20 Computer Architecture November 13, 2013 4 / 56. logoonly Summary Pipelining - Implementation Problem Simple Scoreboard Tomasulo Tomasulo + Speculation Static Sch Dynamic Scheduling RAW forwarding wait (Read) CDB CDB This equation can then be rearranged to find the volume of the CSTR based on the flow rates and the reaction rate: From the definition of conversion, F A = F Ao (1-X) or F Ao - F A = F Ao X, so the equation can be rewritten: Back to the Solution. ?��?�*�B�#�xĐ�%��q��}�տ}}�|�Փ�C=~|��x�h�Ő�;?|��x�w��ןn�?��w��_��Ǔg��w��_�|��yO�?�zu�ډ��Ś�> ��-1�a)0.+�x� ��c�ri��8�ݑ?�R�� <>>> <> T = Clock cycle time. • Describes the performance gains by enhancing one part of the overall system (code, computer) • Amdahl’s Law depends on two factors: – Fraction of the execution time affected by enhancement – The improvement gained by the enhancement for this fraction org … stream 0000005309 00000 n decrease) CPU time: Many potential performance improvement techniques primarily improve one component with small or predictable impact on the other two. <> stream 2 0 obj 0000001509 00000 n 02-1. f~�p��La��"e��q�� 4��e��-)��y��8P��L�,ۿ�'��B$��t-�N�P�ptx�X��ьG�xBU��\��lʳ��j��&��Lԑ� • The CPI can be divided into TWO component terms; The scale factor of workload is also influenced by clock frequency as selected by frequency-selection governors. ��z�z�j1_Үq��?�&��{��Kz��c��8�_�Ϳݮ�8��z��{��?��o��q��X�w��_�t��բ��>)7�_�?�?�|��ts{��+��|�K,娭[p��|��. CPU time for … <> [10] CPU performance analysis a. Formatted 9:28, 16 March 2012 from lsli02. 3 0 obj Execution time: CPI * I * 1/CR CPI = Cycles Per Instruction I = Instructions. t: Cycle time. endobj The model is machine-independent and thus is valid on any uniprocessor. (pD��+�\�b �9��@�PȞ��c Question: Determine the number of instructions for P2 that reduces its execution time to that of P3. Equations: CPU Time = I * T * CPI. Workload Frequency Scaling Law - Derivation and Verification Workload scalability has a cascade relation via the scale factor. CPI: Cycle per Instruction. 6 0 obj oYxO��d�+��q�R��jۍ��n��2��$b>��q�Q�\��}ޢnk'ż"�>9��q�85��ʎ��L��Dk=ur��V�c�2�+��S�r�n�~o'��A�h�8V�L�X�� trailer Background loop with an “observation” variable. 2N��eQ|)�'�� 脁 �T� a�X�@�Ȝ4{9�i��R��XM��t�L�_�3ˉ�b�&B�)ѓzW5B%��d�/�lj��K�!,��>C�q�!`��3X#l�~��T9X�r�.��z�l��b}W�V��\҉� �~�kt��3�'ҏ�>�몥��u���P��C��l�D�9��xE�;�"��a��?ag(k+ vt)4��w�v'��akEsW��.�Ͷ�޵�q�[�W?V��(!U��o;A�g?�K�ٟ��$U��ZԻNI��B`�gi�Tf:N�T��,��Yo}��OgY�D^"��zN��^�/�8G�;'��-��K��'Vϗ�-2dQ�V��%5��HiԡPN�P�L8�Kf9��c�4b��1;��V��zU��榨W?��O��]��>��su&�4�+g��郝嵁*�@BE��4J>q��GY4��js��6U��rYo�ۛ��W�SA��8�,�e掚j�2��i��/=Pwm��j�$��V�_��i��)�媮`�뫗��b5*�U��kM}��M�k�%��̓�7o��U�l��j�>erCt(U��#"��N�� Performance Equation - I • CPU execution time for a program = CPU clock cycles x Clock cycle time • Clock cycle time = 1 / Clock speed-If a processor has a frequency of 3 GHz, the clock ticks 3 billion times in a second – as we’ll soon see, with each clock tick, one or more/less instructions may complete. ��s��co�(�Ϡ�sj#OB��#(\�R�z[� �=A>�a %��X:��C3Ȁ5�;�,��'� ��`��N`��ڛ�/�4��*� ��Oht��s�q�L��7~{;9�z�7j73��ɾ�^-|��Y^�M8�1r��iY��66ӿs׃\��kv�Ĝ6�bz��)y�+�Ӱ1��A��^� Amdahl's law states that the overall speedup of applying the improvement will be: S latency = 1 1 − p + p s = 1 1 − 0.3 + 0.3 2 = 1.18. I know the formula for performance is . To calculate the parallelization efficiency, you need to use a mathematical equation called Amdahl's Law. Previous question Next question. [5] If Computer A executes a program in 19 seconds, and Computer B executes the same program in 25 seconds, how much faster is Computer A than Computer B? <<7e7a3d90fdc37640984a528515d9873c>]>> The discrete time events specified by the clock is known an clock cycles. [10] What is the CPU performance equation, and what do the variables refer to? CPU Time = I * CPI / R. R = 1/T the clock rate. A Note About Instruction Count •. Here, R = Clock rate which can be measured by the inverse of Clock cycle time that means, R = 1/T. t=1/f, f=clock rate. CPU Time = I * CPI/R. Many processors expose performance-monitoring counters that help measure 'productive performance' associated with workloads. <>/Font<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 1024.08 768] /Contents 10 0 R/Group<>/Tabs/S/StructParents 1>> endobj CPU performance equation is one way to start answering these questions. CPU Time = I * CPI * T. I = number of instructions in program. 9 0 obj 6. 2. 0000006470 00000 n Design Alternative 2: Reduce average CPI of all FP instruction to 2. 0000002500 00000 n 0000006068 00000 n Write down the CPU performance equation and deﬁne each of the terms. 02-2. ��m6V�eM8��g�r��g�$z)�4n��#��$�ͅ�U�J�IF}g�F9�07}+�|�;��*��j��ɏ)�yB��3��;5/�gQ�E� �&�Mցpi�LxǨ�ɸF��[{��v':$��:Ezt��h��h>��ɰ��Տ�X -ȟ��OIڷ��~�l��m)�'*E�R�E��\��Hޅ�ҏ�$��)��'��Yז� � �&. Productive performance is typically represented by scale factor, a term that refers to the extent of stalls compared with stall-free cycles within a time window. ȓ�4�Qg��8@�:|��Q��@��@J�п��s�:��F��$��܉�I�͞��j��%�qR����O�--��f� ��'|O�~ NM�\44k�a�K�u��dJAxLI �o](݅",o3��L��I�o`n\gn��d{�O� d�uqQ�o��f��T/�꼪�I�f8��8�%��k~�o��ñ{�oV�Ia�� Latency = InstCount * CPI * cycle time 2. endobj 164 15 endobj CPU Performance Equation - Example 3. What factor(s) can impact those variables? 02-1. endstream endobj �?.yWu��7%>��?=��϶.��+DKG+�΢�z�i}�e$�vi�\�}��@��ͳ�n��?�z}��q�yy�=So~��oWʪЅ�zI=�f��w��ǟ�+� The equation is named after Joseph Boussinesq, who rst derived it in response to John Scott Russell’s observation of the "wave of translation" (also known as a solitary wave or soliton). 1. 166 0 obj<>stream endobj 10 0 obj %%EOF CPU Performance Equation Time for task =C T I C =Average # Cycles per instruction T =Time per cycle I =Instructions per task Pipelining { e.g. 1 0 obj 0000000596 00000 n If 30% of the execution time may be the subject of a speedup, p will be 0.3; if the improvement makes the affected part twice as fast, s will be 2. The performance equation analyzes execution time as a product of three factors that are relatively independent of each other. 5 0 obj ��) WId�hH'��ހ�n� �@��)L��-�� ӤE�� X��b��»��AK �J�]l�is�#q �� L� The performance of a Processor depends on Instruction count, parameter and C view the full answer. Basic Performance Equation. Across the reactor itself equation for plug flow gives, -----(1) Where F’A0 would be the feed rate of A if the stream entering the reactor (fresh feed plus recycle) were unconverted. {�Yux�T�Jx�ny�x�r�Se��M][P"Su� ��'��d �MV�j^��t�Q�?��W�[G{��#6Np)y�e�� endstream endobj 165 0 obj<> endobj 167 0 obj<> endobj 168 0 obj<>/Font<>/ProcSet[/PDF/Text]/ExtGState<>>> endobj 169 0 obj<> endobj 170 0 obj[/ICCBased 178 0 R] endobj 171 0 obj<> endobj 172 0 obj<> endobj 173 0 obj<>stream Many processors expose performance-monitoring counters that help measure 'productive performance' associated with workloads. 4 0 obj Noor Mubeen, Intel. CPU Performance Equation. These combined to form CPU Performance Equation tT = 1 ` £CPI£IC, Analysis of CPU Performance Equation • CPU time = Instruction count * CPI / Clock rate • How to improve (i.e. -��d�h��8�"��2��hPvM��,Xv��kF+��F}��[�)G�ג*`�֤*L�(e? CPU performance equation. x��}[�]9n�{��tH;�� P�v��N�]�.��]��~D~$�u|��v� ~�q�iQ"u�DQ�Ǔ��? CPI = Clocks needed to complete an instruction. 0000002218 00000 n H��W�r�H}�WtռH)�f_I�*Y�k�T��-+��d��()�q�c�{� ݼH��gL��F�i��u�l�䟶��߮��i#��Y��T%��H��lʢ�H�o��4�΋+��?�� *��x'>��Edt�(�R�m�N8��EIl]�8|��V��d�ʄ*�#��`[O!��=��*б*㕉9~��|>W�6��9?�DX�?l��%�`�Z�q͒8I�L�Kl��G��ˋk1��$��KzM81�%�t2{B�l_C;%�� 0000002577 00000 n •“Dynamic”. † Instruction count in the performance equation of CSTR Determined by program, compiler and! Verification workload scalability has a cascade relation via the scale factor of workload is also influenced by clock frequency selected... The CPI for multiplies from 10 to 5 but increases the cycle by! 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