was just wondering whether execution of 5000 lines of code based in a class whihc is called in every file does it take a lot of processing time ?
The number of lines of code is not the determining factor in how resource intensive the script is. It will depend upon how many of those lines are typically executed
and what those lines are doing
. As an example, 1 line of code (infinite loop) would be sufficient to cause excessive runtimes. There are factors that contribute to a perceived long runtime as well, such as a complex (or poorly coded) SQL query or a script that embeds a large file (such as a graphic). In short, neither total lines of code nor download time are accurate indicators of actual CPU utilization.