woz$ perlbrew use 5.18.0
woz$ time perl -CSD registerRecordDeviceDriver.pl softIoc.dbd

real	0m0.461s
user	0m0.380s
sys 	0m0.020s
woz$ perlbrew use 5.20.0
woz$ time perl -CSD registerRecordDeviceDriver.pl softIoc.dbd

real	0m14.656s
user	0m13.548s
sys 	0m0.075s
woz$ perlbrew use 5.24.1
woz$ time perl -CSD registerRecordDeviceDriver.pl softIoc.dbd

real	0m9.518s
user	0m8.977s
sys 	0m0.044s