benfred
Incomplete profiling results
Hello!
I noticed that ~98% of the samples are missing in my case. I cannot share the profile for reasons of confidentiality, but at the process level, I see ~600.000 samples, and one level below it, only ~11.000 samples are left. This happens with the following parameters: py-spy record -r 1 -s.
I intentionally set the sampling rate low because the process runs for about 1 day.
How do you think I should interpret this result? What is my application doing 98% of the time when it is inside the process but not within any function inside that process?
Do you have a reproducing script that you can share ?
Also what operating system, and python version are you using?
Apologies, I cannot share the script, since I developed it for my employer. I am using CentOS 9 stream within a Docker container and the host is using Debian. The Python version is 3.9.
A possible cause, I think, is an app which runs many "active" threads which have no Python context. For example, fully native threads, or threads that run only Cython code.
You can try taking a native profile with perf to see accurately what CPU is spending time on (you'll see if it's native code / Cython / Python interpreter/runtime code, etc).
Do you still see missing samples when using py-spy record --native?
