Hangout Notes 22 June 2017

domagoj@ has some numbers to share and will send a set of measurements along to the group

Apple has added instructions and cycles as variables in their latest seed released at WWDC. Source is not yet available. There is a manual page but no test scripts.

bdkidney@ gave a talk at BSDCan covering the new things that CADETS is doing with DTrace.

markj@ brings up the issue of inline functions being visible but not traceable. gnn@ asks about using the same tricks that are used in the PID provider in user space. markj@ thinks we can target the reduced set of instructions to make this work for inline in the kernel. The code all lives in fasttrap but we want this in FBT.

gnn@ will ask emaste@ about compiling the kernel with LTO to see if that breaks DTrace

bdkidney@ now has LOOM talking to DTrace via the new dtrace_probe() system call

samuel@ is optimizing the unregister call because right now its a linear search and that's…slow. He is also looking at deduping strings in DTrace since they take up a lot of space.