lkml.org 
[lkml]   [2012]   [Jul]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: RAID extremely slow
Date
On Fri, 27 Jul 2012 14:45:18 -0700, you wrote:

>On 07/27/2012 12:08 PM, Bill Davidsen wrote:
>> Have you set the io scheduler to deadline on all members of the array?
>> That's kind of "job one" on older kernels.
>>
>
>I have not, thanks for the tip, I'll look into that now.

Plus I disable the on-drive queuing (NCQ) during startup, right now
I don't have benchmarks to show the difference. This on a six by 1TB
drive RAID6 array I built over a year ago on Slackware64-13.37:

# cat /etc/rc.d/rc.local
...
# turn off NCQ on the RAID drives by adjusting queue depth to 1
n=1
echo "rc.local: Disable RAID drives' NCQ"
for d in a b c d e f
do
echo " set NCQ depth to $n on sd${d}"
echo $n > /sys/block/sd${d}/device/queue_depth
done
...

Maybe you could try that? See if it makes a difference. My drives
are Seagate.

Grant.


\
 
 \ /
  Last update: 2012-07-28 07:21    [W:0.073 / U:0.928 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site