Talk

PC² Kolloquium: User-space Scheduling for Heterogeneous Systems under Linux

Event dates:	12 December 2011 14:00
Organizer:	Paderborn Center for Parallel Computing
Location:	O4.267

Daniel Welp - Diplomarbeit

Applications that exploit accelerator hardware are governed by an individual, technology- specific software interface. No coordination or balancing between different devices is currently possible for these tasks, as up to date versions of the Linux operating sys- tem kernel lack native support for scheduling accelerator-based heterogeneous systems.  Equipping systems with accelerators is a recent trend, evident in research, industry and even in supercomputing, and thus finding a way to support scheduling applications to heterogeneous resources this is a relevant issue.

 

This thesis proposes a user-space scheduler that controls accelerator-occupation for registered tasks. A novel API makes a calling application subject to the decisions of this scheduler that runs as a user-space process. It enables task migration across hardware boundaries to support load balancing and time sharing of resources by employing coop- erative multitasking. An evaluation shows that scheduling heterogeneous resources from user-space is possible and can allow for sufficient scheduling frequencies while maintaining a low CPU-consumption. Two test implementations demonstrated increased

application performance and reduced average job turnaround times on a test system with multiple Intel CPUs and a general-purpose GPU by NVIDIA.