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Re: Some (small) c++ compilation profiling data (oprofile)
John Levon wrote:-
> Again, not really scientific but :
Thanks, this is interesting, but I don't claim to understand it.
> (This is subject to frailties in bfd_find_nearest_line(),
> and the inaccuracy of delayed profiling interrupt delivery ..)
> /* time count, time %age, mem ref count, mem reg %age */
> 141 /* ht_lookup 149193 3.769% 27240 2.39% */
I looked on the oprofile site but couldn't see this format of
output, nor an explanation of what it meant.
However, I guess that the number is a cycle count (or something
equivalent). But I don't understand why there are 2 numbers
and 2 percentages.
> 163 /* 37996 0.9599% 9582 0.8409% */
> 164 for (;;)
I don't understand this either - how can a for statement
be expensive? Looking at the numbers shows this is not
a total for the loop, but is in addition to everything else.