Heterogeneous Heartbeats: A framework for dynamic management of Autonomous SoCs

Abstract

Modern computer systems are formed from many interacting systems and heterogeneous components, that face increasing constraints on performance, power consumption, and temperature. Such systems have complex run-time dynamics which cannot easily be predicted or modelled at design-time, creating a need for online dynamic systems management. The Heartbeats API is a popular open source project which provides a standardised way for applications to monitor and publish their progress in multi-core CPU systems, but it does not allow hardware components to be monitored or to observe the progress of other components of the system. This paper presents work which extends the capacities of the Heartbeats API across the whole system while maintaining backwards compatibility with the legacy software API. To demonstrate the framework's capabilities an Autonomous Underwater Vehicle (AUV) case study is explored, where a power-aware HW/SW image processing application is implemented on a reconfigurable SoC and an approximate energy saving of 30% is observed for an example input video. Current progress is also discussed on some applications which build upon the framework, including an CubeSat experiment for an Adaptive Heterogeneous FDIR system that will launch in 2016 by the European Space Agency.

Application Control and Monitoring in Heterogeneous Multiprocessor Systems

“…This approach can be generalised through a standardised software framework and the use of an application programming interface (API), to enable the exposure of control and monitoring sources from any application. However, current frameworks do not allow the simultaneous monitoring and control of both hardware components and applications at runtime [9]- [13]. Moreover, most existing frameworks do not inherently support HMP platforms or support the management of concurrent applications.…”

“…Knobs allow the tuning of application and hardware parameters by the RTM, while monitors enable the observation of application behaviour (i.e. application requirements) and the measurement of hardware properties by the RTM [4], [9], [10], [15]. In addition, knobs and monitors can been used to explore application-device tradeoffs, such as throughputpower [11] and precision-throughput [7], and locate optimal operating points for applications [16].…”

“…Most of the frameworks are based on the Heartbeats concept and inherit its features, e.g. application monitors [9], [11], [13], [15], [18], [19]. In order to perform tradeoffs within a single application, multiple monitors of different types must be exposed, e.g., throughput, accuracy or error rate, but many frameworks do not support this functionality.…”

“…In addition, for an application to meet its requirements, a target can be specified with the monitor. A small number of frameworks support this feature but they do not indicate as to whether the target is a maximisation or minimisation objective [9], [11], [13], [15], [19]. Furthermore, only some frameworks support concurrent applications, which is a common scenario in real-world systems [10], [13], [18], [19].…”

“…Current frameworks provide partial abstraction of RTM to device communication, but do not include both knobs and monitors to control hardware components at runtime [9], [12], [13], [19]. Moreover, most existing works do not operate on heterogeneous platforms, which provide both highperformance and energy-efficiency by combining conventional CPUs with other accelerators.…”