Oversampling method calls

[vasily-kartashov]

Comparing the profiling output from sample_prof to xdebug it seems that sample_prof oversamples method calls.

[nikic]

It's expected that sample_prof and xdebug provide different results (because xdebug uses an instrumenting profiling mechanism that has a large effect on the cost of certain operations). Depending on the size of the difference it might be a bug though. If you can share example profiles for sample_prof and xdebug I can take a closer look.