hello mat, here comes the results of each action. in all the process i've used the iotop (what a great utility you pointed!), and always saw only the pdflush process acessing the hd. no user interface were used. the apm is set to 128 with hdparm ok, then try the following: you at least should have noatime,nodiratime,commit=600 :) that did the job! also, i've tested without the commit option, which didn't changed the result. enabled for the reiserfs or >=ext3 filesystems you can also try data=writeback (but beware this might put your data at risk !) * can't try select the anticipatory i/o scheduler and set following stuff :( no change. echo "16" > /proc/sys/vm/page-cluster # default: 3 # :( no change. echo "60" > /proc/sys/vm/swappiness # default: 60 # By default, Linux will aggressively swap processes out of physical memory onto disk in order to keep the disk cache as large as possible. # This means that pages that haven't been used recently will be pushed into swap long before the system even comes close to running out of memory, which is an unexpected behavior compared to some operating systems. # The /proc/sys/vm/swappiness parameter controls how aggressive Linux is in this area. :( no change. echo "3000" > /proc/sys/vm/dirty_expire_centisecs # default: 3000 (30 seconds) #2 how long data can be in the page cache before it is considered expired and must be written at the next opportunity. Note that this default is very long: a full 30 seconds. That means that under normal circumstances, unless you write enough to trigger the other pdflush method, Linux won't actually commit anything you write until 30 seconds later. :( no change. echo "6000" > /proc/sys/vm/dirty_writeback_centisecs # default: 500 (5 seconds) #1 how often pdflush wakes up to write data to disk. The default wakes up the two (or more) active threads every five seconds. # suggestion: 6000 (every 60 seconds) :( no change. echo "15" > /proc/sys/vm/dirty_background_ratio # default: 10 #3 Maximum percentage of active memory that can be filled with dirty pages before pdflush begins to write them echo "50" > /proc/sys/vm/dirty_ratio #modified # default: 40 #4 Maximum percentage of total memory that can be filled with dirty pages before processes are forced to write dirty buffers themselves during their time slice instead of being allowed to do more writes. # modified: 50 echo "25" > /proc/sys/vm/vfs_cache_pressure for i in /sys/block/sd*; do /bin/echo "anticipatory" > $i/queue/scheduler done for i in /sys/block/sd*; do /bin/echo "0" > $i/queue/iosched/antic_expire done for i in /sys/block/sd*; do /bin/echo "150" > $i/queue/iosched/read_expire done for i in /sys/block/sd*; do /bin/echo "750" > $i/queue/iosched/read_batch_expire done for i in /sys/block/sd*; do /bin/echo "1200" > $i/queue/iosched/write_batch_expire done for i in /sys/block/sd*; do /bin/echo "1024" > $i/queue/nr_requests done for i in /sys/block/sd*; do /bin/echo "256" > $i/queue/read_ahead_kb done for i in /sys/block/sd*; do /bin/echo "256" > $i/queue/max_sectors_kb done for i in /sys/class/scsi_host/host*; do /bin/echo "min_power" > $i/link_power_management_policy done try to disable each and every unneeded daemon or applets, programs, etc. by using: * powertop * iotop * htop * top * lsof | grep /home * ... -- To unsubscribe from this list: send the line "unsubscribe reiserfs-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html