Hi ianmi,

Page 309 https://dell.to/33ZYCGe

If you deselect the option to Ignore reserved space when calculating available free space (the default), free-space calculations include the space reserved for VHS 

Let us know if you have any additional questions. 

@ianmi,

You need 10% space for performance and upgrade reasons. You can cross 90%, but perfomance would degrade.

https://www.dell.com/support/article/en-us/sln319234/top-tips-every-admin-should-know-to-keep-their-isilon-cluster-healthy?lang=en 

Thanks Josh - we are running OneFS 8.2.2 but there is no option called  'Ignore reserved space when calculating available free space'. I only have (under SmartPool settings):

My problem isn't actually about VHS - InsightIQ seems to be calculating that correctly (green line). It is that the 90% line is calculated on total provisioned where as I think it would make more sense if this was 90% of writable capacity. I would expect the 90% threshold (dotted orange) to always be below the writable capacity so that it shows the capacity management team how much space is left before things become critical.

Knowing 90% of provisioned doesn't help at all.

Ian

Hi PhilLam - thanks for responding. I understand that best practice is to to leave 10% of available space for OneFS to use and included that in my original post. 

Ian