Imho the Benchmark subrutines all give back time in wallocsecs, if cmpthese(); works diffrently you can always wrap it inside timethese(); or another sub that returns time in wallocsec.

This is what perldoc Benchmark tells you about a possible modification of wallocsecs:

 :hireswallclock
   If the Time::HiRes module has been installed, you can specify the
   special tag ":hireswallclock" for Benchmark (if Time::HiRes is not
   available, the tag will be silently ignored). This tag will cause t
+he
   wallclock time to be measured in microseconds, instead of integer
   seconds. Note though that the speed computations are still conducte
+d in
   CPU time, not wallclock time.
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