Wordpress, Function associated to add_filter it call several times

I have problems related to performance in a Wordpress site.

I did a profiling and noticed that a function associated to a filter:

add_filter('sidebars_widgets', 'otw_sidebars_widgets', 100000); (in a plugin directory)

the execution process enter to this function (otw_sidebars_widgets) several times, more than 100!

I put a code to force to enter only once, and ... the associated plugin works well, the page render fast, visually nothing change, so 1 execution was enough.

Why this happened, could be happened with other filters as well? this behavior is normal?

Thanks!

Carlos.

via Chebli Mohamed