Sorry ... sometimes the fingers are too fast ... Again ... I have a HP Proliant ML110 with Fedora Core 2 instaled and 2 IDE HDs with RAID 1 (Software). AH!!! ... I dont speek english ... but I will try ... This is my system ... Product Fedora Core Component kernel Version fc2 Platform i686 - HP Proliant ML110 - P4 3.0Gh HT + 512Mb + 2x120GB IDE Kernel 2.6.8-1.521smp When server start, DMA is enabled at 2 HDs. [root@ml110 bin]# hdparm /dev/hda /dev/hda: multcount = 16 (on) IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 1 (on) keepsettings = 0 (off) readonly = 0 (off) readahead = 256 (on) geometry = 16383/255/63, sectors = 234441648, start = 0 [root@ml110 bin]# hdparm /dev/hdc /dev/hdc: multcount = 16 (on) IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 1 (on) keepsettings = 0 (off) readonly = 0 (off) readahead = 256 (on) geometry = 16383/255/63, sectors = 234493056, start = 0 Sometimes, the message bellow apears in /etc/var/messages ... and multcount and using_dma are disabled (off) Sep 7 22:42:02 ml110 kernel: hdc: dma_timer_expiry: dma status == 0x60 Sep 7 22:42:02 ml110 kernel: hdc: DMA timeout retry Sep 7 22:42:02 ml110 kernel: hdc: timeout waiting for DMA Sep 7 22:42:02 ml110 kernel: hdc: status timeout: status=0xd0 { Busy } Sep 7 22:42:02 ml110 kernel: Sep 7 22:42:02 ml110 kernel: hdd: DMA disabled Sep 7 22:42:02 ml110 kernel: hdc: drive not ready for command Sep 7 22:42:02 ml110 kernel: ide1: reset: success This is the process running on the server: [root@ml110 bin]# ps -ef UID PID PPID C STIME TTY TIME CMD root 1 0 0 10:49 ? 00:00:01 init [3] root 2 1 0 10:49 ? 00:00:00 [migration/0] root 3 1 0 10:49 ? 00:00:00 [ksoftirqd/0] root 4 1 0 10:49 ? 00:00:00 [migration/1] root 5 1 0 10:49 ? 00:00:00 [ksoftirqd/1] root 6 1 0 10:49 ? 00:00:00 [events/0] root 7 1 0 10:49 ? 00:00:00 [events/1] root 8 6 0 10:49 ? 00:00:00 [khelper] root 9 6 0 10:49 ? 00:00:00 [kacpid] root 29 6 0 10:49 ? 00:00:00 [kblockd/0] root 30 6 0 10:49 ? 00:00:00 [kblockd/1] root 31 1 0 10:49 ? 00:00:00 [khubd] root 42 6 0 10:49 ? 00:00:00 [pdflush] root 43 6 0 10:49 ? 00:00:00 [pdflush] root 44 1 0 10:49 ? 00:00:00 [kswapd0] root 45 6 0 10:49 ? 00:00:00 [aio/0] root 46 6 0 10:49 ? 00:00:00 [aio/1] root 156 1 0 10:49 ? 00:00:00 [kseriod] root 198 1 0 10:49 ? 00:00:01 [md0_raid1] root 199 1 0 10:49 ? 00:00:00 [kjournald] root 1442 1 0 10:49 ? 00:00:00 syslogd -m 0 root 1446 1 0 10:49 ? 00:00:00 klogd -x rpc 1465 1 0 10:49 ? 00:00:00 portmap root 1496 1 0 10:49 ? 00:00:00 /usr/sbin/smartd root 1515 1 0 10:49 ? 00:00:00 /usr/sbin/sshd ntp 1544 1 0 10:49 ? 00:00:00 ntpd -U ntp -p /var/run/ntpd.pid -g root 1555 1 0 10:49 ? 00:00:00 gpm -m /dev/input/mice -t imps2 root 1566 1 0 10:50 ? 00:00:00 crond xfs 1588 1 0 10:50 ? 00:00:00 xfs -droppriv -daemon daemon 1598 1 0 10:50 ? 00:00:00 /usr/sbin/atd dbus 1617 1 0 10:50 ? 00:00:00 dbus-daemon-1 --system root 1625 1 0 10:50 ? 00:00:00 [kjournald] root 1633 1 0 10:50 ? 00:00:00 mdadm --monitor --scan root 1652 1 0 10:50 ? 00:00:00 login -- root root 1653 1 0 10:50 tty3 00:00:00 /sbin/mingetty tty3 root 1654 1 0 10:50 tty4 00:00:00 /sbin/mingetty tty4 root 1656 1 0 10:50 tty5 00:00:00 /sbin/mingetty tty5 root 1658 1 0 10:50 tty6 00:00:00 /sbin/mingetty tty6 root 1870 1 0 10:51 ? 00:00:03 [md0_resync] root 1872 1 0 10:51 tty1 00:00:00 /sbin/mingetty tty1 root 1873 1652 0 10:51 tty2 00:00:00 -bash root 1912 1873 0 10:51 tty2 00:00:00 /bin/sh /usr/X11R6/bin/startx root 1923 1912 0 10:51 tty2 00:00:00 xinit /root/.xinitrc -- root 1924 1923 4 10:51 ? 00:00:51 X :0 root 1938 1923 0 10:51 tty2 00:00:00 blackbox root 1940 1938 1 10:51 ? 00:00:14 /usr/lib/mozilla-1.7.2/mozilla-bin -UILocale en-root 1949 1 0 10:51 ? 00:00:00 /usr/libexec/gconfd-2 18 root 1958 1938 0 10:52 ? 00:00:02 gnome-terminal root 1960 1 0 10:52 ? 00:00:00 /usr/libexec/bonobo-activation-server --ac-activroot 1961 1958 0 10:52 ? 00:00:00 gnome-pty-helper root 1962 1958 0 10:52 pts/0 00:00:00 bash root 2023 1962 0 10:55 pts/0 00:00:00 bash root 2072 1958 0 10:55 pts/1 00:00:00 bash root 4667 2023 0 11:09 pts/0 00:00:00 sleep 1 root 4668 2072 0 11:09 pts/1 00:00:00 ps -ef And this is the services running on init 3: [root@ml110 bin]# chkconfig --list | grep 3:on atd 0:off 1:off 2:off 3:on 4:on 5:on 6:off gpm 0:off 1:off 2:on 3:on 4:on 5:on 6:off crond 0:off 1:off 2:on 3:on 4:on 5:on 6:off mdmonitor 0:off 1:off 2:on 3:on 4:on 5:on 6:off mdmpd 0:off 1:off 2:on 3:on 4:on 5:on 6:off random 0:off 1:off 2:on 3:on 4:on 5:on 6:off smartd 0:off 1:off 2:on 3:on 4:on 5:on 6:off xfs 0:off 1:off 2:on 3:on 4:on 5:on 6:off sysstat 0:off 1:on 2:on 3:on 4:on 5:on 6:off rawdevices 0:off 1:off 2:off 3:on 4:on 5:on 6:off portmap 0:off 1:off 2:off 3:on 4:on 5:on 6:off network 0:off 1:off 2:on 3:on 4:on 5:on 6:off ntpd 0:off 1:off 2:on 3:on 4:on 5:on 6:off syslog 0:off 1:off 2:on 3:on 4:on 5:on 6:off readahead 0:off 1:off 2:off 3:on 4:off 5:on 6:off sshd 0:off 1:off 2:on 3:on 4:on 5:on 6:off messagebus 0:off 1:off 2:off 3:on 4:on 5:on 6:off readahead_early 0:off 1:off 2:off 3:on 4:off 5:on 6:off microcode_ctl 0:off 1:off 2:off 3:on 4:on 5:on 6:off I tried disable ACPI on boot, but the error continues ... When it occurs, the system stay very slow ... and if I change the DMA_STATUS to on again, the error occur again ... this is the interval of problem ... Sep 6 05:06:41 ml110 kernel: hdc: irq timeout: status=0xd0 { Busy } Sep 6 09:44:12 ml110 kernel: hdc: status timeout: status=0xd0 { Busy } Sep 6 13:48:27 ml110 kernel: hdc: irq timeout: status=0xd0 { Busy } Sep 7 15:13:36 ml110 kernel: hdc: status timeout: status=0xd0 { Busy } Sep 7 22:42:02 ml110 kernel: hdc: status timeout: status=0xd0 { Busy } Sep 8 01:27:02 ml110 kernel: hdc: status timeout: status=0xd0 { Busy } Sep 8 04:37:02 ml110 kernel: hdc: status timeout: status=0xd0 { Busy } Sep 8 07:52:02 ml110 kernel: hdc: status timeout: status=0xd0 { Busy } Someone know this problem and one solution ... Thanks ... Luciano Andre Baramarchi Joinville - SC - Brazil