Granular Computing

Data centers suffer from low resource utilization because their applications lack fungibility in resource use — the ability to move load quickly across servers without disrupting performance.

Nu introduces logical processes, a new abstraction that splits the classic UNIX process into many atomic units of state called proclets that can be independently and quickly migrated. Logical processes provide fungibility in resource use through this fine-grained, microsecond-scale migration. Thus, we can migrate small units of state of an application quickly, to adapt to the compute and memory resource needs of the moment.

Quicksand builds on this idea to harness stranded datacenter resources — capacity that is left unused because it is scattered across machines in fragments too small or too imbalanced for conventional applications to use — with granular computing.

We are also studying how granular resource demand heterogeneity — fine-grained variation in what different parts of an application actually need — can be exploited for better efficiency.