Nu is a new datacenter system that enables developers to build fungible applications that can use datacenter resources wherever they are—even if they come from different machines—without the need of reserving them, thereby significantly improving resource efficiency. Currently, Nu supports C++ applications.

• Nu: Achieving Microsecond-Scale Resource Fungibility with Logical Processes
  Zhenyuan Ruan, Seo Jin Park, Marcos Aguilera, Adam Belay, Malte Schwarzkopf
  20th USENIX Symposium on Networked Systems Design and Implementation (NSDI '23)
  

This repo contains the DDB-moded Nu runtime, which is a modified version of the original Nu runtime that supports DDB for distributed interactive debugging. To check out the original readme for this repository, please see README_orig.md.

This repo also lightly modified the Caladan runtime, which is used by Nu, to allow the scheduler be aware of the debugger. With this modification, the scheduler will not try to preempt the uthread on the process if the process is paused by a debugger.

To run the debugger-aware mode:

# in "caladan" root dir
sudo ./iokerneld ias dbg

The dbg flag specifies the debugger-aware mode. However, to specify the dbg flag, you need to first specify the schedule policy name, e.g., "ias".