I have the feeling that if I run multiple of my perl scripts under fcgi, my server tends to get unproportional load.

Can someone confirm this? One or two fcgi scripts seem to run fine, making it 3 or 4 seems to be too much... (alhtough their complexity/design is almost the same)
A hint for a memory leak??

Any comments welcome!

As you can see here: http://www.linuxquestions.org/questi...d.php?t=563760, this posting is somewhat related to my other performance problems...

It's actually not all that rare.

Linux/UNIX are "multiuser/multiprocess" operating systems. However, they are designed to run DIFFERENT processes all at once. When you run the SAME process multiple times at once they are each using the same resources (e.g. same file on same filesystem on same disk). It is this that causes processes to cause the system load to increase dramatically.

You can cause this on purpose with a simple shell script:

while true
do find /
done

If you run that in one terminal and top in another you'll see the CPU load increment fairly quickly. The reason is because the first find isn't done before the next one (and the next one and the next one...).

However, there is a simple solution for the above:

while true
do find /
sleep 300
done

The above would make it wait 5 minutes (300 seconds) after the first find until it got to the next find.

Similarly if you had 100 different users all kick off "find /" at the same time it would have pretty much the same result.

So it would depend a lot on what your fcqi scripts are doing. It might be worthwhile to put in simple check how many invocations of your scripts are running and put in a sleep or other governor so that it limits the number that run concurrently.