immense delayed write to file system (ZFS and UFS2), performance issues

[Gerrit Kühn]

On Tue, 26 Jan 2010 19:12:01 -0500 Damian Gerow <dgerow at afflictions.org>
wrote about Re: immense delayed write to file system (ZFS and UFS2),
performance issues:

DG> Adrian Wontroba wrote:

DG> Having a script kick off and write to a disk will help so long as that
DG> disk is writable; if it's being used as a hot spare in a raidz array,
DG> it's not going to help much.

For my RE2 and RE4 disks I wrote a script that calls smartctl -a on all
disks (one after another) every 5s or so. This also prevents the counter
to increase in my setup and you can do it for every disk, no matter if
they are in a raid compound or not. I think writing to the disks may also
fail the desired effect if you have stripes the writes are spead to (raid
50 or similar zpool setups).

Just my 2¢.


cu
  Gerrit