Techniques to Save Energy in Heterogeneous Multicore Architectures under QoS Constraints
نام عام مواد
[Thesis]
نام نخستين پديدآور
Azhar, Muhammad Waqar
وضعیت نشر و پخش و غیره
نام ناشر، پخش کننده و غيره
Chalmers Tekniska Hogskola (Sweden)
تاریخ نشرو بخش و غیره
2019
يادداشت کلی
متن يادداشت
23 p.
یادداشتهای مربوط به پایان نامه ها
جزئيات پايان نامه و نوع درجه آن
Licentiate
کسي که مدرک را اعطا کرده
Chalmers Tekniska Hogskola (Sweden)
امتياز متن
2019
یادداشتهای مربوط به خلاصه یا چکیده
متن يادداشت
Typically, applications are run with available system resources leading to over-provisioning of resources which can lead to high energy consumption. If the computational demand is specified, in terms of a Quality of Service (QoS) contract, it is possible to devote just enough resources to applications and thereby reduce energy consumption. Modern heterogeneous multicore platforms, such as ARM big.LITTLE, typically provide a multidimensional space of resources, called configuration space, such as Voltage-Frequency (V-F) settings, thread count and processor types, which can be configured at run-time to open up new opportunities for resource management. This thesis presents techniques to improve energy efficiency under the constraint of QoS by managing the resource allocation at run-time for applications run on heterogeneous multicore platforms. The applications considered are iterative with a computational deadline associated with each loop iteration. The proposed techniques apply to a framework that uses applications' outer loop iterations as a means for progress-tracking and prediction of the execution time. A first contribution of the thesis is a resource management technique for single-threaded applications that uses core type (e.g. big or little cores) and V-F settings as a configuration space to select a configuration, for each iteration, based on the execution-time prediction of future iterations and computational deadlines. The thesis shows that an energy saving of 25% over the race-to-idle state-of-the-art technique is achieved without missing any deadlines. This scheme incurs only 0.6% and 0.8% of timing and energy overheads, respectively. A second contribution of the thesis is a novel resource-management policy for multi-threaded applications. Here, the configuration space is extended to also consider the thread count, i.e., the number of cores assigned to multi-threaded applications. The proposed technique first chooses the most energy-efficient configuration that meets the computational deadline. Since an iteration typically finishes before the deadline, the proposed technique collects the generated execution-time slack over subsequent iterations with the goal of selecting a configuration that can save more energy. To allow for on-line exploration of the configuration space, at low overhead, a third contribution of the thesis is an online, low-overhead prediction method based on interpolation, that measures the execution statistics at end points of each configuration-space dimension and interpolates the values at intermediate configurations. Overall, the proposed technique saves 61% energy compared to the state-of-the-art race-to-idle technique without missing any deadlines. Further, it only incurs 0.6% and 0.7% of timing and energy overheads, respectively.
اصطلاحهای موضوعی کنترل نشده
اصطلاح موضوعی
Computer engineering
نام شخص به منزله سر شناسه - (مسئولیت معنوی درجه اول )