2011-09-29 02:54 AM
ev1 volume with 1TB without snap space reserve, I try delete all snapshot in volume ev1 but "reserved" did not reclaim space when I type df -r , anyone face this issue before?
===== SIS STAT =====
Path Allocated Saving %Saved
/vol/ev1 801 GB 3686 MB 0 %
/vol/ev1/ev1.lun 861.0g (924521472000) (r/w, online, mapped)
Space Reservation: enabled
Multiprotocol Type: windows
===== DF-R =====
Filesystem kbytes used avail reserved Mounted on
/vol/ev1/ 1073741824 1070461388 3280436 168618224 /vol/ev1/
/vol/ev1/.snapshot 0 0 0 0 /vol/ev1/.snapshot
===== SNAP-RESERVE =====
Volume ev1: current snapshot reserve is 0% or 0 k-bytes
===== SNAP-LIST-N =====
No snapshots exist
ev1 online raid_dp, flex nosnap=on, nosnapdir=off,
sis minra=off, no_atime_update=off,
2011-09-29 05:04 AM
This is correct.
You have set the Fractional_Reserve on the volume to 20%
20% of a 800G LUN is 168G, which is then reserved in the volume space for snapshots of this LUN.
If you do not need to snapshot the LUN, you can set the Fractional_Reserve on the volume to 0% and this will "free" the reserved space as well.
2011-09-29 06:08 AM
Whether you have any snapshot or none, the fractional reserve setting just sets some space aside, for the case that you want to create a snpashot.
It's like a LUN-SnapShot-Guarantee... Which in your case of 20% is not really a guarantee, more a promise
2011-09-29 07:22 AM
I actually agree with Chung - I would expect no impact from fractional reserve if there are no snapshots in the volume.
I vaguely remember some earlier discussions on Community where a 'hidden' snapshot created by de-duplication process was causing something similar.