I was trying to attach node-inspector to a running process and saw something odd – having a group of active processes, each using 10-20% CPU, sending kill -s SIGUSR1 <pid> makes that particular process go to 0% CPU, memory usage would not change either.

I was able to debug v0.10 processes successfully using the same technique.

This is happening on a CentOS 6 (kernel 2.6.32-504.el6.x86_64), node v0.12.7.