I'm currently trying kernel 2.6.1-mm1 with laptop-mode on a reiserfs partition.
If I kill all daemons running on the system and do nothing with it, I can achieve the 10 minutes spin down time I had expected from laptop-mode. However as soon as I start up X with KDE I get regular spin ups every 30 seconds. Looking at the output of "echo 1 > /proc/sys/vm/block_dump", I see an entry every 30 seconds of "kdeinit(15145): WRITE block 65680 on hda1" followed by a whole load of "reiserfs/0(12): dirtied page" and "reisers/0(12): WRITE block XXXXX on hda1".
Due to the regular 30 second interval writes of kdeinit: kded to block 65680, laptop-mode is not particularly usable on this system.
Is this a problem with reiserfs or with kde and is there any fix available?