>Why not? How do you explain it otherwise?

Here I am partially with Gregory: linear small steps smell more like
walking a longer list with empty handles,
adding to an evergroing string and trimming at the end
or similar things. When memory is used up you will run into queries
taking 10000* as long, because there is no more memory left to build a rushmore bitmap.
Program will continue to work - but sloooowly ;-)

>And also, what is the simple test to see if the memory is leaking or not?
Evergrowing sys(1104) return values. Also Calvin has on his blogsite some routines showing the
allocation of the process memory - can be found in one of the sysmetrics offerings as well.

You are EXPLICITLY advised to add such logging to your error handler

HTH

thomas