[email protected] wrote:
> I use 4 disks in a software RAID 5 array.  How
> would one sort out or even find out if this could be the source of a
> problem?

It's pretty easy. Wait until the symptoms occur (by default the mdadm 
package on Ubuntu schedules a rebuild starting early in the AM on the 
first Sunday of the month). Then launch the system monitor from the GUI 
or use the equivalent command line tools (ps or top) to find a process 
with a name like md0_resync and drop its priority to something low, like 
-15. If that resolves the symptom, then you should install a permanent fix.

On my system I modified /etc/cron.d/mdadm to run a few additional 
commands to drop the priority. Onto the end of the existing command 
line, I tacked:
  && sleep 60 && renice 15 `pidof -s -x md1_resync` > /dev/null

and that permanently solved it for me.

Prior to this I spent months playing around with the MD driver parameter 
speed_limit_min, both manually via /proc, and via /etc/sysctl.conf 
(dev.raid.speed_limit_min), but eventually determined that the system 
was CPU bound rather than I/O bound during rebuilds.

  -Tom

------------------------------------------------------------------------------
Apps built with the Adobe(R) Flex(R) framework and Flex Builder(TM) are
powering Web 2.0 with engaging, cross-platform capabilities. Quickly and
easily build your RIAs with Flex Builder, the Eclipse(TM)based development
software that enables intelligent coding and step-through debugging.
Download the free 60 day trial. http://p.sf.net/sfu/www-adobe-com
_______________________________________________
Mvpmc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/mvpmc-users
mvpmc wiki: http://mvpmc.wikispaces.com/

Reply via email to