I ran into a similar problem where the build on my data structure took aboyt 2 minutes, and exiting perl (without exit) took about 23 minutes. I was forced to implement a DESTROY method for one or more objects in the script to 'manually' set each value to undef (I use array refs for objects). The DESTROY method was just a foreach loop. Using DESTROY I was able to cut the exit time to around 9 minutes, which is much better than 23, but still a bit high compared to 2.