When Parallel Speedups Hit the Memory Wall
After Amdahl's trailblazing work, many other authors proposed analytical speedup models but none have considered the limiting effect of the memory wall. These models exploited aspects such as problem-size variation, memory size, communication overhead, and synchronization overhead, but data-acc...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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IEEE
2020-01-01
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| Series: | IEEE Access |
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| Online Access: | https://ieeexplore.ieee.org/document/9078685/ |
| _version_ | 1818557916484993024 |
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| author | Alex F. A. Furtunato Kyriakos Georgiou Kerstin Eder Samuel Xavier-De-Souza |
| author_facet | Alex F. A. Furtunato Kyriakos Georgiou Kerstin Eder Samuel Xavier-De-Souza |
| author_sort | Alex F. A. Furtunato |
| collection | DOAJ |
| description | After Amdahl's trailblazing work, many other authors proposed analytical speedup models but none have considered the limiting effect of the memory wall. These models exploited aspects such as problem-size variation, memory size, communication overhead, and synchronization overhead, but data-access delays are assumed to be constant. Nevertheless, such delays can vary, for example, according to the number of cores used and the ratio between processor and memory frequencies. Given the large number of possible configurations of operating frequency and number of cores that current architectures can offer, suitable speedup models to describe such variations among these configurations are quite desirable for off-line or on-line scheduling decisions. This work proposes a new parallel speedup model that accounts for the variations on the average data-access delay to describe the limiting effect of the memory wall on parallel speedups in homogeneous shared-memory architectures. Analytical results indicate that the proposed modeling can capture the desired behavior while experimental hardware results validate the former. Additionally, we show that when accounting for parameters that reflect the intrinsic characteristics of the applications, such as the degree of parallelism and susceptibility to the memory wall, our proposal has significant advantages over machine-learning-based modeling. Moreover, our experiments show that conventional machine-learning modeling, besides being black-boxed, needs about one order of magnitude more measurements to reach the same level of accuracy achieved by the proposed model. |
| first_indexed | 2024-12-14T00:05:58Z |
| format | Article |
| id | doaj.art-877ca7d6fc7544cabdc974ba59fa104d |
| institution | Directory Open Access Journal |
| issn | 2169-3536 |
| language | English |
| last_indexed | 2024-12-14T00:05:58Z |
| publishDate | 2020-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Access |
| spelling | doaj.art-877ca7d6fc7544cabdc974ba59fa104d2022-12-21T23:26:02ZengIEEEIEEE Access2169-35362020-01-018792257923810.1109/ACCESS.2020.29904189078685When Parallel Speedups Hit the Memory WallAlex F. A. Furtunato0https://orcid.org/0000-0002-4201-0827Kyriakos Georgiou1Kerstin Eder2Samuel Xavier-De-Souza3Diretoria Acadêmica de Informática, Instituto Federal do RN, Natal, BrazilDepartment of Computer Science, University of Bristol, Bristol, U.KDepartment of Computer Science, University of Bristol, Bristol, U.KDepartment of Computer Engineering and Automation, Universidade Federal do Rio Grande do Norte, Natal, BrazilAfter Amdahl's trailblazing work, many other authors proposed analytical speedup models but none have considered the limiting effect of the memory wall. These models exploited aspects such as problem-size variation, memory size, communication overhead, and synchronization overhead, but data-access delays are assumed to be constant. Nevertheless, such delays can vary, for example, according to the number of cores used and the ratio between processor and memory frequencies. Given the large number of possible configurations of operating frequency and number of cores that current architectures can offer, suitable speedup models to describe such variations among these configurations are quite desirable for off-line or on-line scheduling decisions. This work proposes a new parallel speedup model that accounts for the variations on the average data-access delay to describe the limiting effect of the memory wall on parallel speedups in homogeneous shared-memory architectures. Analytical results indicate that the proposed modeling can capture the desired behavior while experimental hardware results validate the former. Additionally, we show that when accounting for parameters that reflect the intrinsic characteristics of the applications, such as the degree of parallelism and susceptibility to the memory wall, our proposal has significant advantages over machine-learning-based modeling. Moreover, our experiments show that conventional machine-learning modeling, besides being black-boxed, needs about one order of magnitude more measurements to reach the same level of accuracy achieved by the proposed model.https://ieeexplore.ieee.org/document/9078685/Parallel systemsdata access delayperformance modelingspeedupmemory wall |
| spellingShingle | Alex F. A. Furtunato Kyriakos Georgiou Kerstin Eder Samuel Xavier-De-Souza When Parallel Speedups Hit the Memory Wall IEEE Access Parallel systems data access delay performance modeling speedup memory wall |
| title | When Parallel Speedups Hit the Memory Wall |
| title_full | When Parallel Speedups Hit the Memory Wall |
| title_fullStr | When Parallel Speedups Hit the Memory Wall |
| title_full_unstemmed | When Parallel Speedups Hit the Memory Wall |
| title_short | When Parallel Speedups Hit the Memory Wall |
| title_sort | when parallel speedups hit the memory wall |
| topic | Parallel systems data access delay performance modeling speedup memory wall |
| url | https://ieeexplore.ieee.org/document/9078685/ |
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