yade-dev team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

I just ran a profiling job, and I have a questionning result.

45% of cpu time is used for the function "mcount" from libc.

According to some googling :

"gcc inserts calls to mcount() at the start and end of functions if 
profiling (-p) is enabled."

That is good, it seems this operation will not take time if profiling is 
disabled (and it takes so much time because of function calls like 
"iterator++" or "body::byId(i)").

But then I have two questions in mind :
1. How comes valgrind/kcachegrind is not removing the time for mcount 
from results? It would make sense.
2. Why could I profile for years without option -p and I could get 
(apparently) consistent results?

Just asking in case somebody knows the answer already.

Bruno

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