Well the faster was compilated with gccversion=3.4.2
the slower with 3.3 20030226(prerelease), two different kernel (!= kernel-headers), two different version of perl....
The slower is compilated with -DUSETHREAD, using multithreading can (not always) reduce cpu-bound performance application on no-SMP machine.
Well, on the other way 30% is more or less the stimated gain from using 3.4 vs 3.3, but this test can be considered a useful test in this direction. If performance is your objective you can googling around for a perl script called cpuflags
and use it's output as compiler flag, but attention some of the flags it suggest can break perl internal semantic.
If you do it please report your success vs. failure.
tried perlcc?