When examining Karlsbakk problem I got into one quite different myself.

I have a 256MB UP PII 933 MHz.
When running the included program with an option of 200
(serving 200 clients with streaming data a 10MB... on first run
it creates the data, from /dev/urandom - overkill from /dev/null is ok!)

ddteset.sh 200
[testcase initially written by Roy Sigurd Karlsbakk, he does not get
into this - but he has more RAM]

the 2.4.18pre7 goes into deep swap after awhile .
It is impossible to start a new login, et.c. finally
the dd processes begins to be OOM killed... not nice...

the 2.4.17-rmap12b handles this MUCH nicer!

/RogerL

--
Roger Larsson
Skelleftea
Sweden