Cooperative I/O: A Novel I/O Semantics for Energy-Aware Applications

In this paper we demonstrate the benefits of application involvement in operating system power management. We present Coop-I/O, an approach to reduce the power consumption of devices while encompassing all levels of the system--from the hardware and OS to a new interface for cooperative I/O that can be used by energy-aware applications. We assume devices which can be set to low-power operation modes if they are not accessed and where switching between modes consumes additional energy, e.g. devices with rotating components or network devices consuming energy for the establishment and shutdown of network connections. In these cases frequent mode switches should be avoided. With Coop-I/O, applications can declare open, read and write operations as deferrable and even abortable by specifying a time-out and a cancel flag. This information enables the operating system to delay and batch requests so that the number of power mode switches is reduced and the device can be kept longer in a low-...

• Type: Conference
• Year: 2002
• Where: OSDI
• Authors: Andreas Weissel, Bjórn Beutel, Frank Bellosa
• Keywords: Cooperative I/o, IDE Hard Disk, Operating System, OSDI 2002, Typical Real-life Programs