This doesn't really have anything to do with vim's Perl support. You
might want to ask on the #vim IRC channel on
irc.freenode.net.
That said, do you mean it does this for every single file? I don't
know what could cause that. Something similar can be done with the
settings 'scrolloff' and 'sidescrolloff', but that also depends on the
size of the window, etc.
If it's just one particular file, maybe you have this in your .vimrc
to make vim remember the last position in the file:
" Jump to the last known position when reopening a file
autocmd BufReadPost *
\ if line("'\"") > 0 && line("'\"") <= line("$") |
\ exe "normal! g'\"" |
\ endif
If you do, you should remove it if you don't like it.