Nimble Sizing

[abraham31]

Hi Folks,

Please  could  you help me size the storage capacity requirements. The client  has  initial  requirement  of 35  TB and  period of investment is for   3 years. The Year on Year growth is predicated at  40 %.He would want   4 daily and 2 monthly snapshots and  the daily  rate of  change is 30 % and monthly is  80 %.  Could  you help me come with the  storage  space required.   The environment   just  has oracle databases.

Regards

varghese

[nmadar105]

Hi Varghese,

Based on the information we have, I made a table for 5 years growth. We made this assumption by using zero copy clone and snapshots and compression of 2:1 for the DB.

Nadav

DB	DB Size (TB)	Year1	Year 2	Year 3	Year 4	year 5	total campus with zero cloning	total campus with zero cloning Year 1	total campus with zero cloning Year 2	total campus with zero cloning Year 3	total campus with zero cloning Year 4	total campus with zero cloning Year 5
Database A	7.5	10.5	14.7	20.58	28.812	40.3368	28.5	39.9	55.86	78.204	109.4856	153.27984
Database B	3.7	5.18	7.252	10.1528	14.21392	19.899488	3.7	19.684	27.5576	38.58064	54.012896	75.6180544
Database C	2.5	3.5	4.9	6.86	9.604	13.4456	5.25	13.3	18.62	26.068	36.4952	51.09328
Database D	4	5.6	7.84	10.976	15.3664	21.51296	19.6	21.28	29.792	41.7088	58.39232	81.749248
Database E	3.5	4.9	6.86	9.604	13.4456	18.82384	14	18.62	26.068	36.4952	51.09328	71.530592
Database F	1.8	2.52	3.528	4.9392	6.91488	9.680832	1.8	9.576	13.4064	18.76896	26.276544	36.7871616
Database G	1.1	1.54	2.156	3.0184	4.22576	5.916064	3.52	5.852	8.1928	11.46992	16.057888	22.4810432
Total	24.1	33.74	47.236	66.1304	92.58256	129.615584	76.37	128.212	179.4968	251.29552	351.813728	492.5392192

[tmcmullin51 · Accepted solution]

Abraham -

I'm not sure where Nadav's info came from, as you provide no such breakdown into individual databases and the initial total only comes up to 24.1 TB, not 35 TB as you stated.

Taken at face value, it seems to me like your initial footprint would have to be:

   35 TB for databases

+ 42 TB for daily snapshots (4 x 0.3 x 35 TB)

+ 56 TB for monthly snapshots (2 x 0.8 x 35 TB)

= 133 TB total

Allowing for 3 years' growth at 40% per year, that becomes:

133 TB at initial install

186 TB at end of year 1 (133 TB x 1.4)

260 TB at end of year 2 (186 TB x 1.4)

365 TB at end of year 3 (260 TB x 1.4)

At this point I usually factor in the best practice of keeping the array below 90% allocation, so that would be 365 TB / 0.9 = 406 TB usable.

If you also want to assume compression of the data, say 2X as Navad indicated, then your requirement would be 406 TB / 2 = 203 TB usable.  I say 'if' here because not all customers like making that kind of assumption, but our InfoSight data actually indicates the average compression ratio for Oracle databases is more like 2.5X.  So 2X reduction is pretty reasonable.

By the way, I don't see how you can have a 30% daily change rate but only 80% change rate per month.  Not saying you're wrong, it just seems counterintuitive to me.  You might want to double-check those numbers with your customer.

I realize this is cocktail-napkin math - and it doesn't address the more important issues of controller selection and cache sizing - but hopefully something here is helpful.