Good motivational video

http://www.youtube.com/watch?feature=player_embedded&v=hV63DbQ_qSc

ProGuard - A case to disable shrink

Assume you are obfuscating a jar in a web application (say you deploy it on machines where you want to protect from decompile+disassembling).

If you come across the error message "The output jar is empty. Did you specify the proper '-keep' options?" , disable shrinking (as you may not have a valid main method entry point in a web application.

How to find if Apache is running prefork or worker MPM

Use the command

apache2 -l

It should list modules like  

 Compiled in modules:
  core.c
  mod_log_config.c
  mod_logio.c
  worker.c
  http_core.c
  mod_so.c

As worker.c is displayed then it uses worker MPM.