[OpenIndiana-discuss] very slow zpool

[Bob Friesenhahn]

On Thu, 31 Dec 2015, Martin Frost wrote:
>
> Any thoughts about what could be causing the slowness?

Run 'iostat -xe' in order to see if a disk is reporting errors or is 
abnormally slow.

Check to see if 'dedup' support is enabled for a zfs filesystem in 
your pool.  For example:

% zfs get dedup tank
NAME  PROPERTY  VALUE          SOURCE
tank  dedup     off            default

If 'dedup' is enabled for the pool then you could suddenly run into a 
performance wall if you don't have enough RAM or dedicated L2ARC SSD 
device.

Bob
-- 
Bob Friesenhahn
bfriesen at simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/