(See the best response by Super Saiyan X.)

Some hours ago, I had quite some lagspikes. It kept on for a minute until I opened up the profiler to see what went on.

I found an empty line (where the proc should be). The rest of the info, CPU time, calls, and whatnot was all functional.
What's causing this? I cleared the profiler, stopped and restarted it, but it didn't show up.
Best response
It can be any kind of instruction... like list().
So there's no way of telling what it actually is? That seems like either something silly or a bug.. Oh well.