It depends. How much control do you have over the web-server? Is your webserver able to run Perl, SQLite and has it all necessary modules and GNUPlot installed? Do you need these charts to be dynamically generated at arbitrary times and for various periods or will you only offer standard charts for fixed periods? Is there enough disk-space available to keep a large number of pre-rendered charts on-line?
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James
My blog: Imperial Deltronics