> effective_cache_size = 1000000 # typically 8KB each
I have this setting on postgresql 7.4.8 on FreeBSD with 4 GB RAM:
effective_cache_size = 27462
So eventhough your machine runs Debian and you have four times as much
RAM as mine your effective_cache_size is 36 times larger. You could
try lowering this setting.
regards
Claus