[2.6.1 vanilla] Accessing CD-ROM drive causes 94% "hi" load

[2.6.1 vanilla] Accessing CD-ROM drive causes 94% "hi" load

[Marc-Christian Petersen]

Hello there,

accessing my CD-ROM drive causes my system to generate 94% "hi" in
top. I reproduced it using the following steps:

1. mount /dev/hda /cdrom
2. cat /cdrom/* > /dev/null

During this timeperiod, the system does almost stop to do any other
I/O, i.e. accessing my SATA drives on an LVM2 stripeset and doing "cat
largefile > /dev/null" does not read the usual 60 MB/s but only like 2
or 3. I am using the anticipatory scheduler, but tried out the
deadline elevator which doesn't change anything.

System configuration:
=====================
/proc/interrupts is at http://home.in.tum.de/foerstes/lkml/interrupts
/proc/slabinfo is at http://home.in.tum.de/foerstes/lkml/slabinfo
/proc/cpuinfo is at http://home.in.tum.de/foerstes/lkml/cpuinfo
lspci -vvv is at http://home.in.tum.de/foerstes/lkml/lspci
dmesg is at http://home.in.tum.de/foerstes/lkml/dmesg
.config is at http://home.in.tum.de/foerstes/lkml/config

I am using a patch for LIRC from:
http://flameeyes.web.ctonet.it/lirc/patch-lirc-2.6.1-rc1-20040106.diff.bz2
Nothing else is patched in.

Is this the expected behaviour of the 2.6 series kernel?

If you need any more informations, let me know.

ciao, Marc

Re: [2.6.1 vanilla] Accessing CD-ROM drive causes 94% "hi" load

[Mike Fedyk]

On Fri, Jan 16, 2004 at 02:48:16PM +0100, Marc-Christian Petersen wrote:
> Hello there,
> 
> accessing my CD-ROM drive causes my system to generate 94% "hi" in
> top. I reproduced it using the following steps:
> 
> 1. mount /dev/hda /cdrom
> 2. cat /cdrom/* > /dev/null
> 
> During this timeperiod, the system does almost stop to do any other
> I/O, i.e. accessing my SATA drives on an LVM2 stripeset and doing "cat
> largefile > /dev/null" does not read the usual 60 MB/s but only like 2
> or 3. I am using the anticipatory scheduler, but tried out the
> deadline elevator which doesn't change anything.

Try hdparm -d1 on your cdrom drive.