Ericsson | August 23, 2011 | Press Release
With so many customer-experience benefits, it is hard to imagine that there are any downsides to smartphones. And yet one common complaint relates to battery life. Ericsson software experts are at the forefront of reducing battery consumption, and delivering other benefits, as part of an EU software research project.
Within the project, known as ACTOR (Adaptivity and Control of Resources in Embedded Systems), Ericsson has coordinated the development of mechanisms for better control of software resources in servers and mobile phones. One desired result is to reduce battery consumption and optimize heat dissipation without any reduction in mobile phone performance.
Johan Eker, a senior specialist at Ericsson Research, coordinated the project.
“ACTOR is about distributing computer processing resources between applications in a way that, for instance, makes it possible to create software that can adapt itself to changes in the environment,” he says.
The majority of the 20 ACTOR participants were students and staff at Lund University in Sweden, Ecole Polytechnique Fédérale de Lausanne in Switzerland, TU Kaiserslautern in Germany, and Scuola Superiore Sant’Anna in Pisa, Italy. Italian company Evidence, which specializes in software for embedded systems, was another key contributor.
“In current systems, resources are distributed by giving each task a specific priority,” Eker says. “The higher priority a task has the more resources it gets. In our model, we think of the central processing unit (CPU) as a big pie chart. Each task is then assigned a slice of this pie, where the size of the slice can be changed dynamically. This gives much better control of the resource usage of a given application, and makes it possible for this to change over time.”
Eker says the ACTOR project has created prototypes to demonstrate potential resource-management solutions, for example running on the ST-Ericsson platform with Android allowing the system to balance performance and energy consumption.
“Battery life is a key element in customer satisfaction for smartphone owners,” Eker says. “So reducing power consumption and extending battery life will improve the end-user experience and encourage even more consumers to opt for a smartphone, boosting operators’ network traffic in turn.”
Eker specifically highlights two ACTOR developments related to the improved resource management results: a new scheduler (SCHED_DEADLINE) for the open-source operating system Linux, which he says was tantamount to building a new heart for the OS, and the creation of tools for multi-core software development.
“For the new scheduler, we decided to work with Linux because of its popularity and wide usage. However, our results can be generalized to any operating system,” he says.
Eker says ACTOR participants worked closely with the Linux community from the outset to ensure that they were on the right track.
“In 2010, we were invited to the Linux Kernel Summit to talk about SCHED_DEADLINE,” he says. “Our ambition is that it will be included in the mainline kernel and Ericsson will continue to support Linux development”.
