The following experimental patch implements token _base_d thrashing protection, using the algorithm described in:         http://www.cs.wm.edu/~sjiang/token.htm When there are pageins going on, a task can grab a token, that protects the task from pageout (except by itself) until it is no longer doing heavy pageins, or until the maximum hold time of the token is over. If the maximum hold time is exceeded, the task isn't eligable to hold the token for a while more, since it wasn't doing it much good anyway. I have run a very unscientific benchmark on my system to test the effectiveness of the patch, timing how a 230MB two-process qsbench run takes, with and without the token thrashing protection present. normal 2.6.8-rc6:       6m45s 2.6.8-rc6 + token:      4m24s This is a quick hack, implemented without having talked to the inventor of the algorithm.  He's copied on the mail and I suspect we'll be able to do better than my quick implementation ... Please test this patch.  include/linux/sched.h |    4 ++  include/linux/swap.h  |   21 ++++++++++  kernel/fork.c         |    2 +  mm/Makefile           |    2 -  mm/filemap.c          |    1  mm/memory.c           |    1  mm/rmap.c             |    3 +  mm/thrash.c           |  100 ++++++++++++++++++++++++++++++++++++++++++++++++++  8 files changed, 133 insertions(+), 1 deletion(-)