I'd guess you've thought of this already, but would it be possible to do

push(@Zeile,$_);
&ZeilenAnalyse;
# and other related code
[download]

inside the script which writes to the log file in the first place? Then you don't need the while loop at all, and more importantly you don't need the repeated open which is presumably what's taking up cpu space.

If that doesn't work, I'd have thought the quick and dirty solution was a sleep n in the while loop so that the open only happens every n seconds, rather than continually.

§ George Sherston