If you want to profile Apache children with LON-CAPA:

1. Ensure that Apache::DProf is installed on your system. If necessary, as root:

   # perl -MCPAN -e shell
   
   cpan shell -- CPAN exploration and modules installation (v1.62)
   
   cpan> install Apache::DProf

2. Add

   PerlModule Apache::DProf

   into loncapa_apache.conf in /etc/httpd/conf/, after the LoadModule for mod_perl.
3. Create the directory /var/log/httpd/dprof and make www the owner.

You may wish to consult the previous answer and wrap this in some other IfDefine, such as PERLPROF.

Then, in /var/log/httpd/dprof, you will get a directory for each PID the server was running under. You'll probably want to use the -X option on apache, so you only get one child, and consequently one directory. Use the program dprofpp in the directory that has the profiler information to read the results of the profiler.

For more information about the profiler, please consult the Internet.