topic Re: 3PAR StoreServ A650 - Calculating usage and overprovisioning in HPE Primera Storage

3PAR StoreServ A650 - Calculating usage and overprovisioning

ColinCallanan — Wed, 06 Mar 2024 09:55:02 GMT

Hi there, I'm looking for some help in calculating overprovisioning % on a primera system.

In the SANXpert tool, we were calculating usage totals for a recent 3PAR StoreServ A650 (2 nodes) on fw 4.5.7.8.

In a recent customer report we saw the following:

Usage Total (Declared: 626688 MB, i.e. 545% of available space)

Reserved Space:

User Used 93813 MB (82%)

User Unused 13963 MB (12%)

Admin Used 0 MB (0%)

Admin Unused 0 MB (0%)

Snap Used 0 MB (0%)

Snap Unused 7168 MB (6%)

Total Reserved 114944 MB (100%)

Overprov. 511744 MB (445%)

Total declared 626688 MB (545%)

The calculations finds that Total declared (626688) is 545.21200% of Total reserved (114944).These numbers come from the following calculations:

Total Reserved is the sum of:

UserUsed
- From the showvv -s table, pull out Thinly provisioned items and sum the Usr Used MiB

UserUnused

From the showvv -s table, pull out Thinly provisioned items and sum the Usr Rsvd MiB and subtract this number from UsrUsed number from the previous step

Snap Unused

From the showvv -s table, pull out Thinly provisioned items and sum the Snp Rsvd MiB

Total declared is sum of VSizeMb

From the showvv -s table, pull out Thinly provisioned items and sum the Total VSize MiB

Percentage of Overprovisioned Space=(Total Reserved Space/Total Provisioned Space)×100%Using the values we initially had:
Percentage of Overprovisioned Space=(626,688 MB/114,944 MB)×100%

Percentage of Overprovisioned Space≈(5.45)×100%≈545%: (edited)

A customer has naturally queried this 545% usage so we need to revisit if there is some obvious mistake in how we calculate this for Primera?

Re: 3PAR StoreServ A650 - Calculating usage and overprovisioning

AnilKT — Wed, 06 Mar 2024 09:35:48 GMT

Hi ColinCallanan,

Overprovisioning Percentage is calculated as (Total Reserved Space / Total Provisioned Space) * 100%

The Total Reserved space as you mentioned is 114944 and the total provisioned space (declared) is 626688.

Overprovisioning Percentage = (114944/626688)*100%

Hope this helps.!

Regards

Anil

Re: 3PAR StoreServ A650 - Calculating usage and overprovisioning

ColinCallanan — Tue, 12 Mar 2024 15:05:59 GMT

Thank you Anil, this makes sense and it simply looks like the previous person who worked on this had inverted the calculations. I have switched it around now and we are testing to see how this works with our previous test cases.

Thanks

Re: 3PAR StoreServ A650 - Calculating usage and overprovisioning

Sunitha_Mod — Wed, 13 Mar 2024 05:16:26 GMT

Hello @ColinCallanan,

That's awesome!

We are extremely glad to know the problem has been resolved and we appreciate you for keeping us posted. Please do let me know if any further help is needed.