2 ms·

https://lwn.net/Articles/499190/ https://lwn.net/Articles/499190/ & https://gnu.wildebeest.org/blog/mjw/2012/05/24/pull-user-space-probe-instrumentation/ https:

• teraflop 11y ago
  Ah, cool. I just tested it out and it seems to work as documented. Unfortunately it requires root access, and incurs about 1 microsecond of overhead per function call on my machine.
  • cthalupa 11y ago
    Reading the X-Ray abstract, unless I'm missing it, it doesn't go into detail about the time overhead. I do see mention of CPU and RAM usage, though. I'm not sure that we have any evidence that X-Ray offers less overhead here, though it's certainly cool if it does.
    • DannyBee 11y ago
      Can you give an example where perf works with 10 million+ probe points? :) (and where this does not have an antagonist effect on the other things on the machine?)