OnCommand Storage Management Software Discussions

volume nearly over deduplicated

Hi experts,

i received an alert that one of my volume is nearly over deduplicated. i can edit the threshold but i am curiious.  I have read that this is a good thing?But is there any drawback to it at all? Meaning a volume getting over deduplicaated?




Re: volume nearly over deduplicated

HI Maico,

The only problem is, if the volume is over deduplicated, and if you wish to un-dedupe the volume would not be able to hold the data.Thats the only downsized I know of.



volume nearly over deduplicated

Thank you!

Re: volume nearly over deduplicated

So, in essence, as long as you can reclaim enough space in the aggregate by reducing the other flex volumes, to allow for the "used" + "saved", you could deduplicate the volume if necessary?

I have increased the dfm thresholds by 10% each from original installation settings already, and will probably do another 5-10% increase, but I'm trying to understand the correletion between 50% saved and 150% deduplicated as shown below? ( it appears the event was triggered during the last pass of sis )

KLNAS1-1> sis status /vol/KW_N1_F1_A1_V7_JDE1_R

Path                           State      Status     Progress

/vol/KW_N1_F1_A1_V7_JDE1_R     Enabled    Idle       Idle for 14:24:10

KLNAS1-1> df -hs /vol/KW_N1_F1_A1_V7_JDE1_R

Filesystem                used      saved       %saved

/vol/KW_N1_F1_A1_V7_JDE1_R/      597GB      587GB          50%



Re: volume nearly over deduplicated

is it as simple as the following?  ( in a case where df - s reports 50% savings on 1000GB data )

df -s shows deduped savings as a percentage of undeduped data   ( 500 used, 1000 data, therefore 500saved/1000 = 50% ), while

dfm option OverDeduplicatedThreshold is calculated by undeduped data as a percentage of deduped space usage  ( 1000undeduped / 500 used = 200% )

Just hoping to confirm/clarify.