Different ONTAP versions show different value for Volume "percent-used" & "percentage-size-used"

RazSK — Wed, 04 Jun 2025 11:07:19 GMT

My previous question was faulty marked as spam. I am trying again...

I am using volume-get-iter ZAPI call and use value of 'percentage-size-used' from volume-space-attributes . As I have noticed on ONTAP 8.3 and 9.2 (I have those two version) I get percentage-size-used as:
"percent-used" = (Used data space + Snapshot Reserve Size) / Total Volume size

However for same ZAPI call on ONTAP 9.7 I get value of percentage-size-used as":

"percent-used" = Used data space / Data sector Size

Then I've tried to run volume show command with percent-used field on those ONTAP versions and noticed same situation.

Here are examples of output of this command:

C-Mode ONTAP 8.3RC1. Size of Snapshot reserve 10%. And it is shown as used space (alongside with used data 200kb which is less than 1%):

The same situation is for ONTAP 9.2:

However for ONTAP 9.7 the Snapshot reserve isn't included in this percentage. The value of percent used shows only data utilization (and snapshot spill, but not snapshot reserve size). Utilization is 3% despite Snapshot reserve is 50%:

Could someone tell from which ONTAP version calculation approach has changed? And point the doc where this is mentioned (because I couldn't find this place at least for now).

Thanks!

Re: Different ONTAP versions show different value for Volume "percent-used" & "pe

Drew_C — Wed, 03 Jun 2020 12:56:12 GMT

The original thread has been restored and can be found here.

This one will be locked to keep discussion consolidated.

topic Re: Different ONTAP versions show different value for Volume "percent-used" & "pe in ONTAP Discussions

Different ONTAP versions show different value for Volume "percent-used" & "percentage-size-used"

Re: Different ONTAP versions show different value for Volume "percent-used" & "pe