Thanks. It's good enough for me to just know where the trigger points are. I think I'll leave the gun in the cabinet. ;)

Romeo

On Tue, Aug 5, 2008 at 7:11 PM, Fox, Adam <Adam.Fox@netapp.com> wrote:

Yes, but it's undocumented and so therefore I'm not sure how supported it is.  Starting in 7.2.4, the threasholds are the following:

 

Volume size < 20GB trigger point is 85%

Volume size 20-100GB trigger point 90%

Volume size 100-500GB trigger point 92%

Volume size 500GB -1TB trigger point 95%

Volume size > 1TB trigger point 98%

 

If you want to tweak these, there are flags in ONTAP that are setable.

 

wafl_reclaim_threshold_t:           tiny vols < 20gb                    threshold = 85%

wafl_reclaim_threshold_s:           small vols from 20gb to < 100gb     threshold = 90%

wafl_reclaim_threshold_m:           medium vols from 100gb to < 500gb   threshold = 92%

wafl_reclaim_threshold_l:           large vols from 500gb to < 1tb      threshold = 95%

wafl_reclaim_threshold_ xl:         xlarge vols from 1tb up             threshold = 98%

 

The idea here is that smaller volumes need a lower threashold because they can fill faster than larger volumes.  98% of  5TB is much more free space than 98% of 5GB.  Setting this value too high can lead to volume full conditions that you are trying to avoid and can be particularly bad if you relying on this to keep space for LUNs in snapshot'ed volumes.

 

You have to use priv set diag to use the setflag command to set these and flags are not persistent so you'd have to set them in /etc/rc if you want these values to survive a reboot.  Something like this should work:

 

priv set –q diag; setflag wafl_reclaim_threshold_<x> 90; priv set;

 

NB:  I am not recommeding changing these values.  Do so at your own risk.  It is not a NetApp Best Practice to change these.  It's a gun.  Be sure to point it away from yourself before pulling the trigger. J

 

-- Adam Fox  
adamfox@netapp.com

From: Romeo Theriault [mailto:romeotheriault@gmail.com]
Sent: Tuesday, August 05, 2008 6:48 PM
To: toasters@mathworks.com
Subject: vol autosize setting?

 

Is there a way to tell 'vol autosize' when it should jump to the next incremental increase. From my tests it look like it increases the volume size to the next increment when the volume reaches around 85% full. Is there a way to change that to say 90 or 95% full?

Thanks

--
Romeo Theriault




--
Romeo Theriault