How can I make my CGI script more efficient when I have to call a C programme using "system"?

[He Nan]

In my script there is a external C programme , I have to call it every time
when the script runs .
But the C programme needs to load big dictionary , the time consuming is
more than 5 seconds .
What should I do to make it more efficient , could I modify the C programme
so that when it runs for the first time , the dictionary is loaded into the
memory and never free until service is shutdown , or shall I try mod_perl to
write a module in c ? I'm confused , for I'm a beginner to CGI programming .