I almost forgot, The maximun number of lines in history is 500 by default, you can decrese that amount by adding this two lines to the profile.
use whatever file editor you are most comfortable with.
since i use emacs i would do the following:
then add this two lines
then saver your changes.
after you've saved your changes do the following
that would set the history file to 50 lines instead of 500
Oh by the way i don't know if under SUSE there is a /etc/profile file.
But just in case there is no profile file you can add those two lines to your .bashrc file. If you don't have a .bashrc file you can create it and then add the lines there.