Wouldn't it be best to use JavaScript for that, since it's client-dependent? I should be able to find some if that's what you're looking for.
Back in my mod_perl days (5 years ago) I used Apache::DProf but that was for the Perl side only.
I'd be wary of any "total time" you get because it's going to involve a lot of factors and may lead you down the wrong path.
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It's sad that a family can be torn apart by such a such a simple thing as a pack of wild dogs